Euno is one such app. It has been around for a while now, and whilst I did have a quick try out with the lite version I always felt that the full version was just too much money.
It went on sale in November with the price coming down to $2.99 from $8.99, and this was in advance of a major update to the app. However, since then there’s been nothing at all. I wonder if we will see an update to this one.