I used to be a terrible photographer when I first started blogging 7 years ago, bad compositions, terrible edit... But I wanted to improve and slowly but surely it happened. It's about always doing the best of your current abilities.
Snapseed is probably the best and easiest to use. You can change basic settings like contrast, saturation and even dodging and burning and there are also pre-made filters to give your photos certain look (under Grainy film).