What API Security Questions Should You Ask Development Teams?

Choosing a development team for your mobile app project feels straightforward until you start thinking about security. Most business owners focus on the obvious stuff—does the team have a good portfolio, can they deliver on time, what's their hourly rate? But then someone mentions API security and suddenly you're in unfamiliar territory. What questions should you actually be asking? How do you know if their answers are any good when you're not a security expert yourself?

I've seen this scenario play out dozens of times over the years. A client comes to me after working with another development team, and when we start discussing their existing app's security setup, there are awkward silences. The previous team never explained their security approach; they just said "don't worry, we've got it covered." That's not good enough anymore—not when data breaches can cost companies millions and destroy customer trust overnight.

The truth is, API security isn't just a technical checkbox that developers tick off at the end of a project. It needs to be baked into every decision from day one. Your APIs are essentially the doorways into your app's data, and if those doorways aren't properly secured, you're inviting trouble. But here's the thing most people don't realise: asking the right security questions upfront doesn't just protect your app—it also reveals how thorough and experienced your development team really is.

The best development teams don't just build secure apps; they can explain their security decisions in plain English and help you understand the risks you're accepting or avoiding.

This guide will give you the specific questions to ask development teams about API security, along with what their answers should tell you about their expertise and approach. You don't need to become a security expert, but you do need to know how to spot one.

What Credentials and Experience Should Your Development Team Have?

When you're vetting development teams for API security, their qualifications matter more than you might think. I've seen teams with impressive portfolios completely botch security implementations because they lacked the right foundation. It's not just about building apps—it's about building them safely.

First thing to look for? Security certifications. CISSP, CEH, or OSCP credentials show a team takes security seriously enough to invest in proper training. But here's the thing—certificates alone don't tell the whole story. A developer with five years of fintech experience who's dealt with PCI compliance will often understand security better than someone with a shiny new certification but no real-world battle scars.

Technical Experience That Actually Matters

Ask about their experience with secure coding practices. Have they worked with OWASP guidelines? Do they understand OAuth 2.0 and JWT tokens inside and out? Can they explain the difference between encryption at rest and in transit without googling it? These aren't trick questions—they're basics that any security-conscious developer should know off the top of their head.

Industry experience is equally important. A team that's built healthcare apps understands HIPAA compliance; fintech developers know PCI requirements. If your app handles sensitive data, you want developers who've navigated those regulatory waters before. Understanding proper app development planning should include security considerations from the very beginning of the project.

• Security certifications (CISSP, CEH, OSCP)
• Experience with relevant compliance standards (HIPAA, PCI-DSS, GDPR)
• Proven track record with secure API development
• Knowledge of current security frameworks and best practices
• Experience with penetration testing and vulnerability assessments

Don't just take their word for it though. Ask for case studies showing how they've handled security challenges in past projects. The best teams will have war stories about security incidents they've prevented or resolved.

How Do They Handle Authentication and User Data Protection?

Right, let's talk about authentication and user data protection—this is where things get proper serious. When I'm vetting a development team, I always ask them to walk me through their authentication strategy first. Not because I'm trying to catch them out, but because how they handle user logins tells me everything about their security mindset.

The first question I ask is simple: "Do you implement multi-factor authentication by default?" If they start talking about how its "optional" or "can be added later," that's a red flag. MFA should be baked into the system from day one, not bolted on as an afterthought. I've seen too many apps get compromised because they treated two-factor authentication as a nice-to-have feature.

But here's what really matters—how they handle user data once someone's logged in. The team should be using proper session management with secure tokens that expire regularly. None of this "remember me forever" nonsense that keeps users logged in for months. And they absolutely must be implementing role-based access controls, so users only see what they're supposed to see.

Key Authentication Questions to Ask

• How do you store user passwords? (Hint: they should be hashed and salted)
• What happens when someone tries to log in from a new device?
• How quickly do authentication tokens expire?
• Do you track and log authentication attempts?
• How do you handle password resets securely?

Ask the team to show you their authentication flow on a whiteboard. If they can't draw it out clearly and explain each step, they probably don't understand it well enough to implement it securely.

Look, authentication isn't glamorous work, but it's the foundation of everything else. A team that gets this right usually gets everything else right too. Don't let anyone convince you that "we'll sort out the security stuff later"—later never comes, and by then it's too late.

What Testing Methods Do They Use for API Vulnerabilities?

Right, let's talk about API testing—because this is where a lot of development teams either shine or completely drop the ball. I've seen apps that looked bulletproof on the surface but had APIs so poorly tested that you could drive a truck through their security holes. It's honestly one of the most overlooked areas in mobile app development, which is mad when you think about it.

Your development team should be running multiple types of security tests on your APIs. We're talking penetration testing, vulnerability scanning, and authentication testing at minimum. But here's the thing—they shouldn't just be doing this once at the end of development. Good teams integrate security testing throughout the entire development process.

Types of API Testing You Should Expect

• Automated vulnerability scans that run with every code deployment
• Manual penetration testing by security specialists
• Input validation testing to prevent injection attacks
• Rate limiting tests to prevent abuse and DDoS attacks
• Authentication and authorisation boundary testing
• Data encryption verification during transmission
• Third-party integration security validation

What you want to hear from your team is that they're using tools like OWASP ZAP or Burp Suite for security testing, and that they follow the OWASP API Security Top 10 guidelines. If they look blank when you mention OWASP, that's a red flag.

Ask them about their testing frequency too. APIs change constantly as features get added, so security testing can't be a one-and-done thing. The best teams run automated security tests with every deployment and do comprehensive manual testing monthly. They should also be monitoring API calls in real-time to catch any suspicious activity that might indicate someone's trying to exploit vulnerabilities they haven't found yet.

How Do They Manage Third-Party Integrations Securely?

Third-party integrations are everywhere in mobile apps these days—payment processors, social media logins, analytics tools, push notification services. You name it, someone's probably built an SDK for it! But here's the thing that keeps me up at night: each integration is basically giving another company access to your app's data and your users information. It's like handing out keys to your house and hoping everyone behaves.

When I'm vetting development teams, I always ask how they evaluate third-party services before integrating them. A good team will have a proper process for checking the security credentials of any external service. They should be asking questions like: What data does this SDK collect? Where is it stored? How often do they update their security patches? Can we limit what data gets shared? The best developers I work with maintain a list of approved third-party services and won't just add something because its convenient.

API Key Management and Access Control

One of the biggest red flags is when developers store API keys directly in the app code. I've seen this more times than I care to admit, and it's bloody terrifying! Any halfway decent hacker can extract those keys and suddenly they've got access to your payment processor or user database. Smart teams use environment variables, secure key management services, and rotate their keys regularly. They also implement proper access controls—not every service needs full access to everything.

The principle of least privilege isn't just security jargon; it's your first line of defence against data breaches through third-party integrations

I always ask teams about their dependency monitoring too. Third-party libraries get updated constantly, and sometimes those updates include security vulnerabilities. A professional team will have automated tools that alert them when dependencies need updating and they'll have a process for testing those updates before pushing them live. Understanding how to handle third-party library updates is crucial for maintaining security over the long term.

Right, so you've asked about authentication and testing—but what happens when something actually goes wrong? Because trust me, something will go wrong at some point. The question is whether your development team will know about it quickly enough to do something about it.

When I'm evaluating a team's security setup, I always dig into their monitoring capabilities. Are they just crossing their fingers and hoping for the best, or do they have proper systems watching their APIs 24/7? You want to hear about real-time monitoring that tracks everything from failed authentication attempts to unusual traffic patterns. If they're not monitoring API response times, error rates, and access patterns, they're flying blind.

What Should They Be Monitoring?

• Failed authentication attempts and suspicious login patterns
• Unusual API call volumes or request patterns
• Error rates and response time spikes
• Database access patterns and query performance
• Third-party integration failures or timeouts
• Data access violations or privilege escalations

But here's the thing—monitoring is only half the battle. What matters just as much is their incident response plan. When an alert fires at 2am because someone's trying to brute force your API, what happens next? Do they have clear procedures for containment, investigation, and recovery?

A good development team will have automated responses for common threats (like rate limiting suspicious IPs) and clear escalation procedures for serious incidents. They should be able to tell you their average response time for different types of security alerts and show you examples of how they've handled past incidents. If they've never had a security incident... well, they probably just haven't been monitoring properly!

How Do They Handle Data Storage and Transmission?

Data storage and transmission are where many mobile apps get it seriously wrong—and where the consequences can be absolutely devastating for both users and businesses. I mean, we're talking about personal information, payment details, and sometimes really sensitive stuff that people trust you with. Get this wrong and you're not just looking at angry users; you're potentially facing hefty fines and legal action.

When I'm evaluating a development team's approach to data security, I want to see they understand the difference between data at rest and data in transit. These aren't just fancy terms—they represent two completely different security challenges that need specific solutions.

Data at Rest Protection

For stored data, your team should be using proper encryption methods. Not some homemade solution they cobbled together, but proven encryption standards like AES-256. They should also understand database security, access controls, and how to properly hash sensitive information like passwords. Actually, if they're storing actual passwords rather than hashed versions, that's a massive red flag right there.

The team needs to know about secure storage options for different platforms too. iOS has its Keychain, Android has the Keystore—these exist for good reasons and should be used for storing sensitive data rather than just dumping everything into a regular database. If your app handles payment information, you'll want to understand whether storing payment details safely is even possible within your app architecture.

Data in Transit Security

For data transmission, HTTPS should be the absolute minimum. But beyond that, they should understand certificate pinning, how to validate SSL certificates properly, and what to do when network requests fail. I've seen apps that fall back to HTTP when HTTPS fails—bloody hell, that's like having a security door that automatically opens when someone jiggles the handle!

Ask to see their data classification system. Good teams categorise data by sensitivity level and apply different protection measures accordingly—not everything needs military-grade encryption, but you need to know what does.

Your development team should also understand compliance requirements for your industry. GDPR isn't just a European problem anymore, and healthcare apps have completely different requirements than gaming apps. They need to show they've thought about data residency, user consent, and the right to deletion. Different platforms may also require different insurance considerations based on their security implementations.

What Documentation and Security Standards Do They Follow?

When I'm vetting development teams for API work, I always ask to see their documentation. Not just the final deliverables—I want to see their internal security standards, their coding guidelines, and how they document their processes. You'd be surprised how many teams go "oh, we keep most of that in our heads" when you ask this question. That's a red flag right there.

Good teams follow established security frameworks like OWASP (Open Web Application Security Project) guidelines. They should be able to tell you exactly which standards they adhere to and why. If they're working in finance, they better know PCI DSS inside and out. Healthcare apps? HIPAA compliance isn't optional, it's the law. But here's the thing—knowing the acronyms isn't enough. They need to show you how these standards translate into their actual development practices.

Documentation That Actually Matters

The development team should provide comprehensive documentation that covers all the important bits. Here's what I look for when reviewing a team's documentation standards:

• API endpoint documentation with security considerations for each route
• Authentication and authorisation workflows clearly mapped out
• Data handling procedures including encryption methods
• Incident response plans with step-by-step procedures
• Code review checklists that include security checkpoints
• Regular security audit schedules and results

I've seen teams that produce beautiful API docs but completely skip the security implementation details. That's like having a detailed map but no compass—it looks professional but won't actually help when things go wrong. The best teams maintain living documentation that gets updated with every security patch and feature release. They treat their security standards as seriously as their code quality standards.

How Do They Plan for Future Security Updates?

Security isn't a one-and-done deal—it's an ongoing commitment that needs constant attention. When I'm evaluating development teams, I always ask how they handle security updates down the line because, honestly, this is where many projects fall apart after launch.

A good team should have a clear update strategy that covers regular security patches, dependency updates, and response procedures for newly discovered vulnerabilities. They should be monitoring security bulletins for all the third-party libraries and APIs they use in your app. It's a bit mad how many teams build apps without thinking about what happens when a critical security flaw gets discovered in a popular library six months later.

One area where teams often fall short is understanding the security implications of cutting-edge development approaches. For instance, AI-assisted coding tools can introduce security vulnerabilities if not properly managed and reviewed by experienced developers.

Update Deployment Process

Ask them about their deployment process for security updates specifically. Do they have automated testing pipelines that can quickly validate security patches? Can they push emergency updates without breaking existing functionality? The best teams I work with have staging environments that mirror production exactly, so they can test security updates safely before rolling them out to users.

Security updates should never be treated as optional maintenance—they're the immune system of your mobile application

Long-term Security Planning

You also want to know about their long-term security roadmap. How do they stay current with evolving security standards? Do they regularly audit their code for outdated practices? A team that thinks about security planning will have processes for regular security reviews, penetration testing schedules, and clear communication about what security updates mean for your app's functionality and user experience.

Look, I'll be honest with you—API security isn't just a technical checkbox you tick off during development. After years of building apps and seeing what can go wrong (and trust me, things do go wrong), I can tell you that asking the right security questions upfront saves you from some pretty nasty surprises down the road.

The questions we've covered aren't meant to intimidate your development team or turn you into a security expert overnight. They're your safety net. When you ask about authentication methods, vulnerability testing, and data protection practices, you're not being difficult—you're being smart. Because here's the thing: your users trust you with their information, and that's not something you can take lightly.

What I've learned from working with different teams is that the best developers actually welcome these questions. They want to talk about their security practices because they're proud of the work they do to keep your app safe. If a team gets defensive or tries to brush off your security concerns with vague answers? That's a red flag right there.

The mobile app landscape changes constantly, and security threats evolve just as quickly. But if your development team has solid answers to these questions—if they can explain their authentication approach, show you their testing processes, and demonstrate how they'll keep your app updated—you're in good hands. Your app will be built on a foundation that can handle whatever comes next, and honestly, that peace of mind is worth its weight in gold.