Its a malaysian Trumpet Snail or MTS as theyre called on here. They can be good or bad. if you dont mind them theyre ok. If you are trying to grow a carpet plant, they can be a nuissance as well as exploding in population at times.
They are not hard to manage and IMHO the benefits outweigh the negatives.
Once every 60days I put an Algae wafer in a fishnet over night. The next morning it's full of snails. I remove the largest one (reproductive size). I return the little ones so the can continue to clean the tank.
I look at it as just another part of the tank maintenance program.
Also, some is always looking for them if you might prefer to sell/trade/give them away vs. kill them.