Which Quell Memento levels have been solved 'better than perfect'?

What is the different between 'Quell' and 'Quell+'?

Ideas for next Quell game

The official solution to 'Carousel' [Guiding Spirit - Stage4, Level 4] is wrong

When I installed / updated the game, I got an error message 'Package File Invalid'. How do I fix this issue?

I've played Quell Memento only. Are there more games?

When is Quell Memento going to be available?

I've played Quell and Quell Reflect. Is there more?

Need help on a particular level?

I can't download Quell or Quell Reflect from Google Play!