Blobula

Blobula is a mixture of action and puzzle gameplay, where you have to clear
levels by removing colored balls, which have to exit through appropriately
colored holes. The balls cannot be hit directly but must be hit using a
smaller ball using a mouse or a stylus. If the action becomes too hectic a
glue-like substance can be released which slows down balls that enter it.

There are special challenge levels with special rules that vary from the
normal levels.