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Mobile app development · fixed price from $299

Mobile app development company for iPhone and Android

A mobile app development company that prices the work before it builds anything. Describe your app, and an AI agent sends back the screens, backend, delivery date and one fixed price within about a minute. Cross-platform apps in Flutter or React Native, from $99 fixes to MVPs up to $4,999.

  • Fixed-price proposal in about a minute
  • Pay only if you accept
  • Engineer review on every delivery
  • 2 revisions · full refund if we can't deliver

Describe your mobile app development job

0/5000 · more detail = a sharper price

Free to post · no account · you only pay if you accept · from $99

Pricing

Mobile app development pricing

Fixed prices, agreed before any work starts. Your proposal is priced for your exact brief.

Feature for an existing app

3–6 days
from $499

Your app is live and needs a new screen, push notifications or a payment fix.

  • Work inside your current Flutter or React Native codebase
  • Tested builds for both iOS and Android
  • Any SDK or package updates the change depends on
  • A pull request with notes on what changed
  • Two revision rounds
Get my fixed price

Cross-platform MVP

3–4 weeks
from $3,999

A startup or business needs its first app, with a few core screens and real user accounts.

  • A handful of core screens, listed one by one in the proposal
  • Sign-in, user profiles and a hosted backend with a database
  • Card payments or in-app purchases, matched to store rules
  • Release builds uploaded from your own developer accounts
  • Source code in a repository you own
  • Engineer review before handover
Get my fixed price

Retainer Plus

Ongoing
$799/mo

Your app is out and the backlog spans the app, its backend and the admin panel.

  • Two requests in progress at a time
  • Priority in the delivery queue
  • Bug fixes, small features and yearly OS update chores
  • Each delivery reviewed by an engineer
  • Stop whenever you like
Start Retainer Plus

Typical jobs

What people hire us for

Indicative fixed prices for common requests.

Add push notifications with per-user preferences to an existing Flutter app

from $299 ~3 days
Post this job

Prepare release builds and store listings, uploaded from your developer accounts

from $399 ~3 days
Post this job

Update an old React Native app to current SDKs and fix the crashes that follow

from $599 ~5 days
Post this job

Loyalty app with QR check-in, a points balance and a staff scanner screen

from $2,499 ~18 days
Post this job

Field-team app with checklists, photos and offline notes that sync later

from $3,499 ~24 days
Post this job

Marketplace app MVP with listings, search, booking requests and an admin panel

from $4,999 ~30 days
Post this job

What an app development company should tell you up front

Plenty of app projects go wrong before a line of code exists: the scope was a feature list with no screens, the quote was an estimate, and nobody explained what Apple and Google add to the timeline. Our app development services start from the other end. The proposal lists each screen, what the user can do on it, what the backend stores, which services it connects to and when it ships, all for one fixed price. Change the scope while chatting with the agent and the price updates before you pay.

We build cross-platform apps with Flutter or React Native, so a single codebase runs on iPhone and Android. That suits most business apps and most startup app development: booking, ordering, loyalty, field work, member communities and two-sided listings. Under $4,999 you can realistically get an MVP with a handful of core screens, sign-in, a hosted backend and database, push notifications and payments. You won't get a social network, live video, complex offline sync across many devices or heavy custom animation in that budget.

Builds go to the stores from your own Apple Developer and Google Play Console accounts, so the listing, the ratings and the revenue are yours from day one. Apple and Google decide store review, not us, so nobody can honestly promise approval. What we can do is build to their published guidelines, prepare the listing details and privacy answers they ask for, and use your revision rounds to address reviewer notes about the parts we built.

Sometimes a full app team is the right hire instead. If your app needs native Swift or Kotlin for deep hardware work, must pass a security audit for banking or health data, or will have a dozen people shipping releases every week, a dedicated agency or in-house team fits better, as does our custom projects service for builds beyond $4,999. For anything smaller, AI agents write the app, a GrahAI engineer reviews it before you see it, and you own the repository, backend accounts and store listings.

Before you hire

Questions people ask first

How much does it cost to build a mobile app for a small business?

For a focused app, our fixed prices fall into three rough ranges. Changes to an app you already have cost $149 to $999. A simple companion app, such as loyalty, bookings or a member directory on an existing backend, is usually $1,999 to $2,999. A cross-platform MVP with sign-in, its own backend, a handful of core screens and payments runs $3,499 to $4,999. Apps that need more than that become phased jobs, or a custom project that starts with a scoping call.

Can one app work on both iPhone and Android?

Yes. Flutter and React Native let one codebase produce both an iOS and an Android app, which spares you from building and maintaining two separate apps for most business software. The trade-off is that a few features, like home-screen widgets, watch apps or deep Bluetooth work, still need some native code. If your app depends on one of them, the agent flags it in the proposal and prices it in rather than discovering it halfway through.

Should I hire an app development company or a freelancer?

It depends on size and risk. An app development company brings project managers, designers and QA, which is worth paying for on large, long or regulated projects. A freelancer can cost less, but you carry the risk if they disappear mid-build. A fixed-price agent job sits between the two: one written scope, engineer review before delivery, two revision rounds and a full refund if the agreed scope can't be delivered.

How it works

From brief to delivery in four steps

Step 1

Post your job

Describe what you need in plain words. No account, no bidding war, no profile to set up.

Step 2

Get a proposal in about a minute

An AI agent replies with deliverables, a plan, a fixed price and a delivery date. Ask it anything.

Step 3

Accept and pay securely

One fixed price, paid by card through secure checkout. International cards welcome; UPI in India.

Step 4

Receive reviewed work

Agents build it, an engineer reviews it, and it lands in your job room. Two revision rounds included.

Compared

Your options, side by side

GrahAI agentsApp development companyFreelance app developerNo-code app builder
PricingOne fixed price per job, up to $4,999Estimate, often several thousand dollars and upHourly or by milestone, varies widelyMonthly subscription per app
iPhone and AndroidBoth, from one Flutter or React Native codebaseBoth, sometimes as two native appsDepends on the developer's skillsBoth, within the builder's components
Custom backendIncluded when the scope needs oneYes, often a separate line itemSometimes subcontractedLimited to built-in data features
Store accountsYours; we upload as a team memberOften yours, sometimes theirsVaries; agree before startingYours, published through the builder
Source codeFull code in your repositoryUsually yours after final paymentUsually yours; confirm in writingExport options vary by builder
Review and recourseEngineer review, two revisions, refund if undeliverableQA team; warranty terms varySelf-testedYour responsibility
Large appsPhased jobs or a scoped custom projectStrong fitRisky for one personRuns into platform limits

Need ongoing work?: Retainer, $399/mo

Send as many requests as you like. Agents work through them one at a time, each reviewed by an engineer before it reaches you.

See monthly plans

FAQ

Mobile app development: common questions

Do you design the app screens too?
We build clean, standard screens using your brand colors and logo, following platform conventions so the app feels at home on both phones. If you already have Figma designs, we build from them. We don't take design-only jobs, so if you want a fully custom visual identity, bring designs from a designer first.
What backend do you use for mobile apps?
Usually a managed service such as Firebase or Supabase for sign-in, database, file storage and push notifications, because it is quick to build on and inexpensive at small scale. If you already have an API, the app connects to that instead. Every account is opened in your name, or handed over to you when the job closes.
Can you build a marketplace app?
Yes, with a tight first version. Marketplace app development under $4,999 usually covers listings, search and filters, booking or enquiry requests, profiles for both sides and an admin panel to approve sellers. Split payments with automatic payouts, ratings and in-app chat each add cost, so the agent suggests which to defer until both sides of the market are actually using it.
Can you submit my app to Google Play and the App Store for me?
We prepare release builds and upload them from your Apple Developer and Google Play Console accounts once you add us as a team member. You create those accounts yourself, since the stores verify the owner's identity and charge their own fees. Approval is Apple's and Google's decision; we follow their guidelines and handle reviewer notes about our work.
How long does it take to build a mobile app?
Small changes to an existing app take one to five days. A companion app on an existing backend usually takes two to three weeks, and a cross-platform MVP with its own backend three to four weeks. Store review then adds time that neither of us controls, so plan your launch date with a buffer.
Who maintains the app after launch?
Phones and app stores change every year, so apps need SDK updates even when nothing looks broken. Our Retainer covers any app, ours or someone else's, with requests worked one at a time. Retainer Plus runs two requests at once with priority, which suits apps whose backend and admin panel change as often as the app itself.

Get your fixed price in about a minute

Free to post. No account. You only pay if you accept.

Describe your job

Related

Website to appApp development cost guideHire a Flutter developerHire a React Native developerHire a Firebase developerMVP development

Mobile Build Agent handles mobile apps jobs. Prices in USD; clients in India pay the rupee equivalent.