Android App ID Generator

What an application ID is

The application ID — historically the "package name" — is the string Android uses to tell one app from another. Two apps with the same ID are the same app: installing the second replaces the first, and Google Play refuses a second listing with an ID that already exists. It is written in reverse-domain form, com.company.product, because domains are already globally unique and reversing them puts the broad part first. Nobody checks that you own the domain; the convention exists to keep IDs from colliding.

The rules

• At least two segments separated by dots; three is conventional.
• Each segment starts with a letter and contains only lowercase letters, digits and underscores. No hyphens, no spaces, no uppercase.
• No segment may be a Java keyword: new, class, default, package, int and so on. com.new.app fails; com.newapp.app is fine.
• Google Play additionally rejects IDs beginning with com.example, com.android, android, java and javax.

The generator folds your app name into a valid segment (spaces and punctuation removed, a leading digit dropped, a keyword suffixed with "app") and either reverses your domain for the prefix or uses com.yourname.

It is permanent — choose it once

The ID is baked into every APK you build and into the Play listing. Change it and you have a different app: existing users keep the old one, do not receive updates, and the Play Console treats the new ID as a brand-new submission with a new review, new listing and zero installs. Even a "fix" from com.myname.app to com.myname.recipes breaks that link. Pick something you will be happy with in five years, and then leave it alone. The updating guide explains what must stay the same between builds.

What to avoid

Do not put a version in it (com.myname.app2), the word "test" or "demo" unless it is one, or anything that reads as another company's brand — Google's review will bounce com.google.anything and can suspend an account for impersonation. If you build several apps, share the prefix: com.myname.recipes, com.myname.timer, com.myname.notes.