You can create new folders using the "+" button in the bottom toolbar.

Yes, I plan to add support for the document picker and iCloud Drive.

iOS 8 still has some keyboard bugs - especially when using the split keyboard on iPad.

Another user reported a workaround:

1. Merge the keyboard and put it back at the bottom.
2. Kill Textastic from the task switcher.
3. Restart Textastic.

Please let me know if that helps.

Yes, I'm working an an update to fully support the new iPhone models. I'll receive my own iPhone 6 Plus for testing tomorrow and have been using an iPhone 6 for about a week.

Thanks for letting me know! I also saw in my tests that iOS 8 still has some issues with the on-screen keyboard - especially when using the split keyboard. Apple probably changed a lot under the hood when they added support for custom system-wide keyboards, so there are still a few bugs that should be fixed in the following releases.