Read people, read
Its crazy how few people actually read anything these days. Yes, this app doesnt do much for a 6S/6S Plus, but they never said it did.
What this app DOES do is give you the model identifier, which then lets you determine the cpu maker (just google it, you can find the list of identifiers lots of places).
Macrumors did a disservice by pointing readers here without explanation, but dont blame the app for their mistake.
pufferdude about
Lirum Device Info