[Galaxy Note 3 General] oalex:
Then you are the same as me. Only 3 difference is that I am 3 years younger and probably much more fat, as I gained a lot of weight after quiting smoking, this is what I am getting rid of now. All these logging of data and smartphone stuff is a nice motivation. You see how you are getting better and stuff.

This one is one of the more popular one: http://www.amazon.com/Wahoo-Fitness...1089144&sr=1-1-catcorr&keywords=wahoo+cadence

$40, this is generally the price range. This is the one I personally have BTW and its perfect. I dont own a GN3 yet, just GN2 (which doest have ANT), so i used it with Sony Active. I hope to get the GN3 soon.

You also have at least 10 more manufacturers to chose from. like Timex, Gamin(yes Gamin has ANT sensor), Bontrager, etc. You can find a comprehensive list of them here. Just select speed an cadence at the side bar and yo get a list? http://www.thisisant.com/directory/

About the above link (Wahoo on Amazon). Two things:

1. Dont be confused. It is an ANT sensor, even tough its not indicated in the name. It just say for Iphone 4 (which I think had ANT in it or with dongle). This sensor is compatible with anything ANT+. So is every other sensor that is an ANT transmitter, it is universal (except for that one sounto that someone mentioned above which is something different).

2. If you go for the Wahoo one, make sure you order the right one. There are 2 versions and it rather confusing. The one I linked (Wahoo Fitness Speed & Cadence Sensor for iPhone) is for ANT, the other one (Wahoo Fitness Blue SC Cycling Speed & Cadence Sensor for iPhone) is for Bluetooth LE (which in fact, to make the story more confusing, will work with GN3 aswell when the bugs are sorted out).

I hope I was able to help. I know it can be a lot of information...

P.S: do you have a link for the app you mention, I dont think I have heard of it. I know Runtastic Road Bike Pro, but nothing Racing Bike Pro. It is important for you to note that if you are actually referring to the Runtastic one, then you dont have and option for cadence. Its very stupid of them actually, the iphone version of thier app has cadence but the android does not. Also the speed meter will be ignored, they will just use gps. The best app out there is hands down IpBike, but the UI is very dated so you might not like it (but is functionality is you only consideration then it cant be beat), the one that have cadence and speed are: Strava (it has it own app, just look), Endmondo, also there are some others.

EDIT: Just remember another app that you might like. SportyPal. Asper UI I think its one of the best. Real dashboard type. Also has the cad and speed and rest. One down side is that it is subscription based and multilevel too. First you buy the basic app, then you buy the Bike addon app. Then the subscription is similar to Endmondo and strava.

But check out the dash board, really cool I think: https://play.google.com/store/apps/details?id=com.sportypalpro&hl=en

There is also a cool demo video you might want to watch. You slide right or left to see the map (you dont need to look at that all the time anyway).

Its rather good at setting goal, like how far you want to go or how many calories you want to burn. Also good at keeping you in your preferred HR range (this depends if you wan to loose weight or do Cardio training).

Here is the bike addon: http://www.sportypal.com/Store/Details/24

http://www.youtube.com/watch?v=ffiY1WUi5_M