For $5 I bought 3 sets from eBay - the red heart/blue filter lens combo, the polarized lens & the star burst lens. I took a few pictures at my local train station so you could see the effects on a plain picture.
Here is the picture without any filters:
Lens #2 - Blue Filter: This one didn't ring my bell in any way, it gives the picture a blue/green tint but its nothing you cant get from holding a piece of cellophane over the camera.
Lens #3 - Star Burst: I liked this one a lot! I like how the border makes the surrounding picture look like its moving. This one will be great to play with when focusing the picture on one person - so many ideas bubbling around in my head!
Lens #4 - Polarized: This one will be great when taking photos that have a lot of glare in them (like shop windows etc) but for everyday life it wasn't so great.
All in all I think for the price they were fun to play around with, but on a practical level they aren't so convenient to keep sticking onto your phone every time you want to take a picture! But hey, buy a set & make up your own mind :) Sunny xx