Hey, as far as I know there are two worthwile android apps for playing go for beginners:
- Go free (I think this one might offer the lower settings out of the two)
- CS lite (or Crazy Stone lite)
both are free and offer some very low AI levels (don’t believe the actuall rank numbers, they are VERY approximate). The most notable difference is that CS offers also 19x19 games while for Go free they are paid. I do not know any such programs for PC, but if you are at the computer I recommend playing humans 
it’s the most fun and there are tons of people of a similar level to yours and it is best to improve if you find someone to improve with. Also we can easily review your games afterwards if you want and point out the places you need to work on.
You can also check this topic: