Professional photographers use filters that attach to their camera lens to create various effects in their photos. You can do the same by making detachable filters for your phone's camera. It's easy and inexpensive.
Now comes the fun part. You can experiment with a wide range of materials to add to your filter base. Each material will make your photos look different. Some materials I've tried are colored nylons, latex gloves and colored celophane.
For this filter, I chose red nylon. To add the material to the base, just cut a small swatch and tape it to the base with clear tape. Make sure the material is taped so that it covers the entire hole in the center of the base.
Now attach the Velcro on the filter to the Velcro on the phone case. Slip your phone into the case and try out your filter.
To make colorful cellophane filters, tape a piece of clear cellophane from a food wrapper to a filter base. Then, color it with a marker. You can make the filter a solid color or several different colors.