I've played with it a bit. You are right in that the desktop app is different. In essence the desktop app is simply a replacement for the USB teather for the EOS utility whereas the app is less functional and somewhat crippled by being only for tiny screens on smartphones.
I was very excited when the sample shots for the EOS remote showed support for the 7D and disappointed when the actual released and subsequent upgrades did not support the 7D with the WFT (especially after buying the WFT
I do also have a 6D and have tried out the EOS Remote but the killer use AFAIK would be to be able to wirelessly tether an iPad in the field using the FULL resolution of the Retina display for checking critical focus for Macro. I'm getting older and need glasses now, the knees don't work as well so I'm a lot slower bending down to peer through an angle finder when I've got the legs splayed out on the tripod and am shooting flowers or other things close to the ground.
I did use the EOS Remote App the other day to take a couple of photos of a Think Tank Mirrorless Mover 10 to post on the EOS M forum here but that was mainly to play and as I use the iPad for random surfing a lot so being able to shoot the images using a 17-40 on the 6D mounted on a gorilla pod and then import them as JPEGs and crop them on the iPad was convenient.
The downside of the WFT and the WiFi enabled 6D is getting different profiles setup for ad-hoc (device to device) and infrastructure (device to access opine or wifi router) connections. The interface is a little clumsy and and must be confusing for people who don't work with these kind of things all the time.
I do a lot of event and I have thought about locking down a body somewhere with a wide angle set to the whole stage or portion of interest then have an assistant take shots. The issue, like you have mentioned, is the App is still immature and this shows in it being awkward and clumsy to use. Also I would hate to have to give up my 6D for this as then I'd be stuck with the much worse high ISO performance of the 7D or using my 1Ds Mk II which while has even worse high ISO compared to the 7D has that authoritative shutter snap that really annoys soloists when you get in tight to the stage. So locking down the 7D and using the pairing to the EOS Utility on a laptop would probably be better ( or just using an intervalometer).
I did think about using the remote app the other night when the lunar eclipse occurred. It was cold here and I thought it would be a good way of keeping an eye on things and picking shots off but I don't have a tracking rig and even with a grip with two fresh batteries I could see three hours of live view draining the batteries and necessitating changing them out which could affect focus and framing. It was moot point though as it was overcast and there was noting to see.
I have used the 6D wireless for copy work and I like that but again it's paired to the EOS Utility rather than the EOS App. My longest USB cable is 8' and sometimes I need more length depending on what I'm set up for. Using the WFT on the 7D I usually use the Ethernet port for tethering as I have lots of long cables and I'd rather be wired than wireless especially when I have lots of copying to do.