Hi,
Yes. iPhone version is still in development. For iOS we don't have Drive/Dropbox autobackup. But you can set iCloud backup for the app. There is also manual backup there. 

Do you mean on the list here: Menu / Vehicles or at Dashboard dropdown?

Merge is not possible currently in Fuelio :(

It canb be bug with Android Auto. Is it working from phone's notification?

Costs type.

Go to Cost Log / right corner - there's Cost types editor

I'm not sure if this is trhe right approach. Reminders if they are done. you need to check the as set as done and add new on instead of editing existing.

Yes. Editing existing is firing next iteraition if that was set. 

Maybe you can tell me more about the use case. Why you are doing that.

Hi. What is cost model? You can remove anything you are adding in the app so I think it's possible. Just define what is cost model.

Maybe you have missed fillup on your log? Without seeing the data it will be hard to tell. 

You need at least two full fillups to see consumption. First full fillup is initial and setting control point. For the second one you'll see consumption.

You need to uncheck - Use device settings. It's using your phone's global settings for locales