Basically your product predates theirs and you have a case. Also let the lawyers handle any communication as you may be stepping out of bounds. (let them handle it)
And be happy that someone is copying you, It's a sign of flattery. Plus they have made their Android users as a few marketers for you for free. Every time an Android users comes in contact with a iphone user who appreciates that app they will look for it in the iphone app store.
good luck.