The 12 questions
- Show me three Mini Apps you built that I can open now. Live apps on your phone beat portfolio screenshots.
- How do you validate initData? The answer should mention HMAC with a key derived from the bot token and server-side checks on every request.
- Which payment rail do you use for digital goods? The only correct answer for in-app digital goods on mobile is Telegram Stars.
- How do you handle the iOS keyboard and fullscreen viewport? Vendors who have shipped will have stories; others will have blank looks.
- Which Telegram clients do you test on? iOS, Android, Desktop, macOS, Web A and Web K; ask to see their device matrix.
- How do you prevent cheating in games or referral fraud? Server-authoritative state, vesting, anomaly detection.
- What is your pricing model? Fixed price after discovery, T&M with reports, or dedicated team; beware of fixed prices without a written scope.
- Who owns the code, the bot and the hosting? You should, from day one, in your accounts.
- What happens after launch? Support plan, SLA, how they handle Telegram client updates.
- How do you communicate? Written status, demo cadence, overlap with your time zone.
- Can you work with our legal and compliance requirements? Contracts under your jurisdiction, GDPR, crypto regulations where relevant.
- What would you cut from my scope to launch sooner? A good vendor has opinions about MVP scope.
Red flags
- Portfolio of websites and native apps but no Mini Apps you can open.
- Card checkout for digital goods inside the app.
- “We will test on Android, iOS is the same.”
- A fixed price quoted from a one-paragraph brief.
- Code or bot registered in the vendor’s accounts.
- No mention of initData, Stars or the SDK in the proposal.
Comparing proposals
Put proposals side by side on scope (screens and features listed), assumptions, timeline with milestones, price per milestone, exclusions, support and IP terms. The cheapest proposal is often the one with the most missing items; the most expensive is not necessarily the most experienced in Telegram specifically.
How we answer these questions
Our process page covers discovery, fixed pricing, demos and ownership; the pricing page shows ranges before any call; and the Mini App development page lists what is included. Ask us the twelve questions; we expect it.
* All prices and ranges on this page are indicative. The final cost is calculated for each project individually and depends on the complexity of the task, the number of developers and specialists required, and the delivery timeline you set. Use the ranges to understand the typical bracket, not as a fixed offer; the fixed price is confirmed in writing after scoping. Read our pricing terms.