Mobile apptestingservices for iOS and Android.

Our QA engineers test your app on the devices and OS versions your users have, check key flows for usability, run regression on every build and prepare each release for App Store and Google Play review.
Test my app

On mobile, a bug isn't a ticket. It's a rating in the store.

Users can't refresh a broken app. They uninstall it and leave a rating every future user will see. Mobile testing has to cover the devices, OS versions, networks and interruptions your users actually live with, before each build goes live.

Why mobile apps are hard to test

01

Too many devices

Screen sizes, chipsets and manufacturer skins change how the same build looks and behaves.
02

OS updates break things

A new iOS or Android version changes permissions, background rules or UI, and your app has to keep up.
03

Store review rejections

A missed guideline, a login that fails for the reviewer or missing privacy details pushes the release back.
04

Crashes you can't reproduce

Crash reports point to a line of code, but not to the device, state or steps behind it.
05

Real-world conditions

Weak networks, incoming calls, low battery and app switching break flows that work fine at a desk.
06

Old versions stay installed

Not every user updates, so your backend and new builds must keep working with what's already out there.

Signs your app needs dedicated mobile testing

If any of these show up in your reviews or crash reports, testing is behind your release pace.

1

Ratings are dropping

Reviews mention crashes, frozen screens or features that stopped working after an update.

2

Bugs on some devices only

Support reports issues your team can't reproduce on their own phones.

3

Crashes spike after releases

Each new build brings a new jump in your crash reporting.

4

Store rejections delay launches

Builds bounce back from review and planned release dates slip.

5

Users drop off in key flows

Sign-up, onboarding or checkout lose people, and nobody knows where it gets confusing.

6

Developers test on one phone

Releases are checked on the newest iPhone and whatever Android device happens to be nearby.

What we test

Mobile QA for every build you ship

Functional testing

Every feature checked against requirements on iOS and Android, including edge cases and error paths.

Device and OS coverage

A device matrix built from your user data, so testing matches the phones your customers carry.

Usability testing services

Walkthroughs of key flows to find confusing steps, unclear copy and places where users get stuck.

Regression testing

Regression runs on every release candidate, so updates don't break what already works.

Crash analysis

We reproduce crashes from your reports, find the steps and devices behind them and write a clear ticket.

Network and interruption tests

Behavior on slow or lost connections, during calls and notifications, and when users switch apps.

Store release checks

Pre-submission checks against App Store and Google Play rules to avoid preventable rejections.

Mobile test automation

Automated checks for stable flows in your CI, next to manual testing of new features.

What our mobile testing covers

Every test plan is built around your users' devices and the flows that matter most to your business.

Devices and OS versions

Device list based on your analytics

Current and older iOS and Android versions

Phones, tablets, screen sizes and orientations

Usability

Walkthroughs of onboarding, sign-up and checkout

Confusing screens, unclear copy and dead ends

Basic accessibility such as text size and contrast

Stability and crashes

Crashes reproduced from your reports

Interruptions, backgrounding and low memory

Slow, unstable and lost connections

Store release

App Store and Google Play guideline checks

Permissions and privacy descriptions

Release candidate sign-off

Platforms and tools we test with

We test native and cross-platform apps and work in the tools your mobile team already uses.

Swift
SwiftUI
Kotlin
React
Xcode
Android Studio
Postman
Jira
GitHub Actions
CircleCI
Who is this for

For teams with an app in the stores, or about to be

Startups before launch

Your first release has to pass review and survive the first wave of real users.

Product companies

Your app ships often, and regression on two platforms takes too long in-house.

SMBs with a customer app

Customers order, book or pay through your app, so a broken build costs money.

Agencies

You build apps for clients and need independent testing before hand-off.

What do you need tested?

A new app before launch

A full test pass and store readiness.

An app with falling ratings

Find what's behind the bad reviews.

Every release

Regression testing for each new build.

A redesign

Usability checks on the new flows.

A crash spike

Reproduce and document the crashes.

A new OS version

Check your app before users update.

How we test your app

01

Product review

We study your app, users, analytics, store reviews and crash reports to see where the risk is highest.

02

Device matrix and plan

We agree the devices, OS versions and flows to cover and how deep testing goes for each release.

03

Test design

We write test cases and checklists for features, usability, interruptions and store requirements.

04

Testing and reporting

We test each build and log defects with device, OS version, steps and a screenshot or recording.

05

Regression and release

Before submission we run regression and store checks and give you a clear go or no-go.

How we work

Choose where to start

Mobile app audit

Quick Audit: 3 working days. Full Audit: 8–10 working days.

Fixed price, agreed before we start.

For apps with unclear quality, falling ratings or an inherited codebase.

Review of crashes and store reviews

Testing of key flows on real devices

Usability findings

Prioritized list of issues

Recommendations for your release process

Audit my app

Ongoing mobile QA

most popular

QA engineers testing every release

Monthly, per engineer.

For apps that ship regularly on iOS and Android.

Device matrix based on your users

Testing of every build

Regression before each release

Store release checks

Crash reproduction and reports

Test every release

Mobile apps we've helped ship

AI CONSUMER APPS

AI Mobile Editors

Global
4M+
DOWNLOADS COMBINED
Before
→
after
↓
Existing  codebase required stabilization
↑
Both apps stayed instore
↓
AI features broken or misleading
↑
AI rebuilt to production quality
↓
App Store compliance at risk
↑
App Store compliance restored
↓
Reviews declining fast
↑
Product stabilized 
EdTech

A mobile app to develop brain functions

4 mo
to a full iOS app on the App Store
Read the case study →

Make the most of the experienced team

We are a global team of
creative
and
strategic thinkers
who specialize in building custom digital products
from scratch. Our main goal is to
deliver high-quality solutions
that meet our clients' needs.
We are a global team of
creative
and
strategic thinkers
who specialize
in building custom digital products
from scratch. Our main goal is to
deliver high-quality solutions
that
meet our clients' needs.
Learn more
85%
recurring customers
12M
the biggest fundraising round by one startup
X3 MRR
growth of partner's business in 5 mos
2 weeks
for project start
5+ years
av. partnership duration with SMBs and product companies

Why Gilzor

We've built iOS and Android products for 7+ years. Our testers know how mobile apps fail because they work next to the developers who build them.

What we bring

Mobile experience

7+ years of building and maintaining iOS and Android products.

Native and cross-platform

Swift, Kotlin, React Native and Flutter apps.

Fast start

Testing can start in about two weeks.

On-time delivery

98% of our projects are delivered on time.

An audit when you need one

Quick and Full mobile app audits for an outside view before ongoing testing.

What makes us different

Your users' devices

We choose devices from your analytics, not from a generic list.

Usability, not just bugs

We flag flows that work but confuse people.

Developer-ready tickets

Every defect comes with device, OS version, steps and a recording.

Store-aware testing

We check review guidelines before submission, not after a rejection.

Overlap with US hours

Our engineers in Europe overlap with part of the US working day.

What our clients
frequently ask

Do you test on real devices?

Yes. We test on physical iOS and Android devices and use simulators and emulators to extend coverage across OS versions. The device list is agreed with you based on your user data.

How do you decide which devices to cover?

From your analytics and store data: the models, screen sizes and OS versions your users actually have. If you're pre-launch, we start from your target audience and adjust after release.

What does usability testing include?

Our testers walk through your key flows as new and returning users, note where steps are unclear, slow or easy to get wrong, and suggest specific fixes. It complements, not replaces, research with your own users.

Can you help with App Store or Google Play rejections?

Yes. We check builds against store guidelines before submission and, if a build was rejected, help find the cause and verify the fix.

Do you test React Native and Flutter apps?

Yes. We test native Swift and Kotlin apps and cross-platform React Native and Flutter apps, on both platforms.

How is mobile app testing priced?

Audits are a fixed price agreed before we start. Ongoing testing is billed monthly per engineer. Tell us about your app and release rhythm and we'll send a quote.

No sales pitch

Tell us about your app

Share the platforms, your users' devices and what worries you most. We'll suggest a test plan and a quote.

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