ummm ummm ummm i know this, can't remember!! will get back to you with a name, think it's a pest snail though
edit - found it!
from rain's pinned topic on snails
Bladder/Tadpole/Pouch Snails - Family Physidae
Size: 9 - 15 millimetres ; 0.3 - 0.6 inches
Physa, Physella, Aplexa, Stenophysa, first two ones being the most common subfamilies. The one in the picture is most likely Physa fontinalis. Physids consists of several different species and subfamilies, they all have sinistral shells (when you keep the snail towards you and the spire pointing up, the shell lip/opening points to the left), thin tentacles and they don't usually grow over 2 centimetres/0.8 inches. They are also hermaphroditic and pulmonate, no operculum. They do take air to their lung and you can see them rising to the surface regularly. They also have two hand like mantle lobes extended against the outer side of the shell on both sides of the snail to give more area for exchange of oxygen and carbon dioxide.
Physids and Lymnaeidae snails can easily be mixed with each other, they look almost the same and act the same. They also lay same kind of eggs. Clear eggs are inside a jelly like clear clutch and the clutch is usually horseshoe shaped, might be straight too. The eggs are laid on plants, decoration and even on tank walls. You can and you should remove the eggs when you spot them. These can reproduce really fast and might do damage to live plants. Can tolerate brackish water.