I used to use Mousewaits and DL Wait Times, but since Disneyland released their own official app, that's pretty much the only one I use. It has the current wait times (fairly consistent with what you'll find on the times boards in the parks and at the ride entrance, but there is about a 5 minute lag between when times are updated on the boards and when it shows up on the app) and current FP return times (that seems to lag about 10 minutes in this case).