Small things that save an afternoon
4 tools for Flutter and Android developers. Free, no account, and they run in your browser — built because I needed them while making the templates.
Play Store Signing Key Generator
Fill in your app details and get the exact keytool command, key.properties file and Gradle signing config for a Flutter or Android release build.
Open →Firebase & Maps Cost Calculator
Estimate what a delivery or marketplace app costs per month — Firestore reads and writes, map loads and Routes calls, at current list prices.
Open →Package ID Renamer
Paste a new bundle id and get the exact files, lines and Gradle values to change in a Flutter or Android project.
Open →AdMob Test ID Cheatsheet
Copy-paste Google test unit ids for banner, interstitial, rewarded and native, for both platforms.
Open →Why these exist
Every one of them started as something I looked up more than twice while building the templates in this catalog — the keytool invocation nobody remembers, the AdMob demo ids buried four clicks into Google's docs, the Firestore arithmetic that decides whether an idea is affordable before a line of it is written. Extracting them into a page was faster than searching again.
Nothing you type leaves your browser
All four run entirely client-side. There is no account, no rate limit, and no request to a server carrying what you entered — which matters most for the signing-key generator, since the details you put into it end up inside a certificate you are about to trust for the life of the app.
The long-form version
Need the whole app rather than a piece of it? Browse the templates by what you are building.