It might help others diagnose but here's the 411 on phones.

1. They only last a few years it seems. Of a few feet to the pavement.
2. When they are messing up you try a factory reset.
3. Just like our PCs we backup what we can't lose so item 2 is never a concern.
4. Full make and model along with age and story such as "my dog got it and carried it around for a day."