Development notes

Coding style

• Prefer initializing properties inline over spelling them out in a separate init { block.

• Use annotations (@Foo) only when it makes the code easier to read.

• Prefer references (Foo) over nullable references (Foo?).

• Prefer variable names which are not keywords over working the problem around with backticks ('is').

• Prefer constructs like foo?.let { over non-null assertions (!!).

Complex parts of the app

The app code is quite simple, this is just fancy stopwatch after all. But some parts are nontrivial:

• Making sure that the timer doesn't stop, by launching a proper background service was hard to figure out.

• The icon was surprisingly challenging to add, mostly because every SVG editor will just scale your image, but exactly scaling is ignored by Android Studio's SVG import.

• The recycler view was tricky to set up: most examples are overcomplicated, when really what was needed here is just an adapter and a holder class.

Kotlin

If you are used to Java, then not spelling out type names all over the place is confusing in Kotlin. See https://stackoverflow.com/questions/54851861/how-do-i-activate-type-annotations-hints-in-kotlin-like-depicted on how to let Android Studio show these types for you without polluting the code.