Reading a software licence without a law degree

Every listing here shows a licence. Using an app on your own phone is fine under all of them. The differences mostly matter if you want to change or share the code.

GPL and AGPL let you use, change and share the software, as long as what you share stays under the same licence. LGPL applies similar terms to the library itself but is looser about the software built on top of it.

MIT and Apache-2.0 are permissive: you can do nearly anything with the code if you keep the licence notice. MPL-2.0 sits in between and applies file by file.

Some licences aren’t open source at all. Sodium’s Polyform Shield licence lets you read the code and use the mod, but it limits competing uses. This is a short guide, not legal advice, so read the licence itself before you reuse any code.