A numeric-only keypad (much like the dial-pad in the phone app or the keypad in a calculator) would have bigger key and thus be easier too handle.

I have an Prius Plug-In car that I charge daily in my garage. I would usually only get the electricity consumption value monthly when the bill arrives. The gasoline fill up is occurring less frequent than that. So my question is what mileage should I indicate when entering the monthly electricity bill? It's not that clear how the average fuel consumption is calculated in such a scenario.

I have permanent discounts on some fuel stations. For instance: in Poland with Karta Dużej Rodziny I have 10gr discount on LPG on Orlen and 8gr discount on Lotos. Currently, the ordering of stations by price is incorrect and therefore unusable. Is it possible to add a setting of permanent discounts for specific companies, eg Orlen or Lotos fuel stations.

It would be nice to have an option to export statistics section to PDF file. 

For a while now (I guess a couple of months) syncing between different Google Drive accounts is impossible.

We are two people A and B (with 2 separate Google Accounts) sharing one vehicle. So we created a setup so that person A syncs the data with her Google Drive, which created the familiar /Android/Fuelio/... folder structure. Then the /Android/Fuelio folder was shared to person B with full access (including edit) permissions. In B's Drive account the shared Fuelio folder was moved to /Android/ and could be used as if it was her own. This is how it perfectly worked (even before the beta sync option was added, making sure one pulled in new data before adding data and uploading).

Now, person A can sync to and from her own Google Drive without problems. These changes are also reflected in the shared folders in person B's Drive account, when accessed directly via Google Drive. However, whenever B wants to sync to or from her Drive account using the Fuelio App the existing (shared) data are ignored and new (unshared) folders are created (with exactly the same names) right beside the shared ones. So when trying to download from the shared Google Drive before uploading anything, B get's the error message "No files in folder" [1]. Which makes sense insofar as the newly created empty nonshared folders are really empty. But what used to work and really is wanted, is to not ignore the existing shared folder structure and use it instead of creating new empty folders.

Person A also tried sharing only the /Android/Fuelio/sync folder or even just the individual files in that folder: sync.dat and vehicle-1-sync.csv. (And of course B moved them to their respective locations in the - newly created by Fuelio - folder structure.) All to no avail, none of them were used by B's Fuelio App, instead giving the aforementioned "No files in folder" message.

Here is a Google Drive screenshot of person B's /Android/ folder with the newly created emtpy Fuelio folder owned by himself (top, selected, info on the right) and A's shared Fuelio folder (bottom).

Both A and B are using the latest Android version 6.3.0. I'm also happy to supply further information if needed.

[1] To be exact the message was in German: "Keine Dateien im Verzeichnis."

no one has wrote the praise yet, so i thought like i must right one, this deserves one.

Excellent and fluid UI: the UI is excellent and fluid, follows the android guidelines. the charts really looks crisp and intuitive.

the Costs module with Pro version is excellent.

Also the sync features with dropbox and drive. 

and Best of all, the app does not keep on running in background! i like it

I see an issue with the mileage calculation. when i enter the first full fill up, there is no mileage associated with that, which is correct. But on subsequent fill   ups, the mileage should be calculated for the last fill up, instead of current fill up. because with the current fill up i'm providing the actual distance the car traveled for the last fill up. So the calculated mileage should be pushed down to last fill up and current fill up should just be without mileage calculation. 

i have created a simple excel with the same algorithm.

Please see if you find it useful