It's been a long time coming. 5.3 has been uploaded to Google Play. You can get the apk from github:

https://github.com/spacecowboy/NotePad/releases

I'm still not satisfied with Dropbox stability so that stays in the beta version for now.

Changelog:

# New features:

## Synchronize your notes to the SD-card
Saves your notes as text (.org) files. Combine with apps like OwnCloud or BitTorrentSync for an alternative to GTasks.

# Other changes:
* Date and Time selectors now use the new Google calendar style
* Fix a bug with scrolling in the preferences
* Many other tweaks and fixes.
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