>What's the best way to handle multiple user's requesting a record? I have heard that you can write a value out to the record, like the user's Id, but what happens if the app crashes?

I'm not sure what you're asking. Usually querying the same record isn't an issue - it's updating and dealing with conflicts. Is that what you're asking about? For update conflicts you can usually add a timestamp field and use that as part of the update query in addition to the primary key: the update will fail if it has been changed since when you first retrieved it.