[dustingetz]

For apps that read a lot more than they write, there exist ACID databases in which reads don't have to touch network, while retaining consistent writes. Datomic is one; for those who have never studied datomic, the database storage is immutable in the same way that Git commits are immutable, which enables a lot of git-like things in your database, like queries without network. That way your apps can be fast without giving up ACID.

I don't know if anything like Datomic exists on mobile; and OP is talking about mobile apps not webapps; so OP may be kind of correct, at least today.

[ericsink]

I need to look at Datomic.

Zumero could also be described as having similar characteristics as Git. It's like a DVCS, except for stuff that looks like rows and columns instead of stuff that looks like directories and files.

I'm sure that any decentralized database violates ACID in some way, but Zumero is pretty darn ACIDic. All the local CRUD operations are ACID. And the sync to the server is ACID, or highly corrosive at minimum. But yes, the two operations are separate.