Can anyone recommend an editing app-preferably free that will do the basics-colour, crop, brightness, straighten etc. I’ve tried a few but they all seem to bombard you with pop-ups or are optimised for i.phone.
I normally use picasa which is great for everything except straighten which bizarrely blurs the picture slightly.

Snapseed.

The photoshop express app works well too

SnapSeed seconded. Excellent app.

Oh boy, that Snapseed is so good-ta muchly.