That snail is fine (it looks like a gilled pond snail), most snails are fine, as stated before; they are really just clean up duty. A few species eat plants, but most eat detritus, microscopic bacteria, and algae.
As for population booms, as long as there isn't excess nutrient available to them, the population will remain small, as it's numbers are limited by competition for food.
I got some stowaway snails on some limnophila that I really enjoyed until my loaches ate them. The loaches were so tiny when I got them and the snails lasted a while. Loach mouths finally got big enough to make short work of some escargot. I knew this day would come.
...Snails can play an integral part in disposing of uneaten food and keeping your tank clean. Getting rid of all snails is silly, in my opinion....
My Snails get at algae my Cherrry Shrimp, Amano Shrimp and SAE can't get at. I would not have a planted tank that doesn't have some snails to help keep it clean. in a well balance system they don't get out of hand fast. When there are more than you might want an algae wafer in a fish net is all you need as a trap.
Mistakes can include but are not limited to: Not having a balance between lighting/ferts/CO2 that can cause an algae explosion (food source), overfeeding because they think their livestock is hungry all the time, not caring for plants and allowing them to rot (decaying plants = food source), not removing dead livestock (food source).
My point is that most people freak out because they think they're a bad sign. In reality, snails in moderate numbers are a sign of a healthy and thriving aquarium.
Many people think they're unsightly and some can be. But I'd rather have a bunch of snails to clean up my mistakes than worry about a few dozen baby snails blocking my chance at a better tank photo.
Honestly, I like having snails. Sure, they might be "annoying" to some, but I find them to be pretty good looking actually. I've noticed that bladder snails come in all different colors and I've seen some with dark blue bodies and black shells with yellow webbing, which looks pretty cool if you ask me. You also get Ramshorns which some people buy fancy color mutations of. My ramshorn populations are now mainly leopard patterned or showing a high amount of red coloring. MTS I just like because they shift through the substrate and make sure it stays healthy.
All of them make short work of extra food and I even go out of my way at times to feed them. Unless you are wanting to only keep nerite snails or something, I wouldn't mind having the other common hitchhikers what so ever.