2 Questions Please! Mobile Link / Cadence Numbers

New to Zwift so please be gentle!

Loving it so far but I have 2 questions:

My setup is a Tacx Flux trainer with the iOS app connected by Bluetooth & then AirPlay to TV.

  1. My cadence numbers seem very erratic, I don’t have a Cadence sensor set up (mine is a Garmin so only works on ANT+). I’m anywhere from 70rpm to 130rpm whilst still pedaling roughly the same on the trainer. Would a Bluetooth sensor on my crank such as the Wahoo be more accurate to “override” the Zwift estimation?

  2. I’ve downloaded the Mobile Link app which I use on my iPad & use my iPhone to AirPlay. The app works fine but when I’m on a course & come to a turn I can’t work out how to use the Mobile Link app to do a turn? Is this possible?

Thanks for your help!

Hi Ian, I wanted to set mine up on the cheap and i dont have a bike computer, so followed one of the youtube zwifting guides and borrowed an old tacx non-smart trainer, bought a bluetooth cadence and rpm combined sensor from Ebay for about £6, that links in perfectly to the MobileLink on ios.  I’ve added my existing Garmin HR band with ant+ to an old laptop to get my heartrate and that all links to an old 42 TV screen - i don’t get any irregularities in readings, apart from once where the bluetooth signal just dropped (maybe interference). I’ve never enjoyed spending so much time in my garage!  

When I improve, I might splash out for a proper setup, but for fitness this does the job and as long as the readings are consistent will provide a good gauge to improvement.

If you swipe the mobilelink screen left or right once you’re riding, you’ll see the u-turn symbol on the screen with all the other shortcuts.  You have to be going at minimum speed (i think its 5mph) and you have to press and hold the u-turn key.

I hope this helps.

Good morning Ian, 


Welcome to Zwift. 

Let me see if I can help:

  1. Your assumption is correct, since you don’t have a cadence sensor your Cadence is all over the place, I think your trainer is sending something to Zwift. I would suggest getting a cadence sensor that will make it a lot better.

  2. on the Zwift mobile Link app (ZML) at the bottom you will see little Icons, there a bunch of them if you swipe left. Once you get to a turn you will see little arrows tap on them to change direction.

Hi both.

Thank you very much for your replies.

The app turning question, I managed to work out for myself this morning!

As for the cadence, the numbers also seemed a lot more realistic as well on my session this morning. I did most of it (it was hilly) in the small ring rather than the big so maybe that made a difference. I have a Tacx Flux so I’m presuming Zwift reads the cadence from that but I still feel a separate cadence sensor “should” be more accurate.

The trainer is brand new so maybe needs a few km’s to settle in but it’s something to keep any eye on.

Thanks again!

The trainer use an formula to estimate your cadence, based on power fluctuations. as you pedal your power goes up and down with every pedal RPM (when your feet are at 12 and 6 it is lower then at 3 and 9).

It is better than noting. the good news is that Cadence numbers don’t effect your power numbers or performance.

Thanks Gerrie.

I’d be correct in saying that a Bluetooth sensor on the crank would be more accurate as it would send that reading direct to Zwift?

100% correct.



Thanks for your help Gerrie.

I can only use the game through iOS at the moment so unless I got an ANT+ dongle my Garmin cadence sensor won’t work.

Looks like Wahoo will have to take some more of my money!

No the Garmin is ANT+ so it wont work. I found some cheep Blue tooth cadence sensors on E-Bay. 


Thanks Gerrie.

Bluetooth HRM is 1st on my shopping list & then cadence sensor to follow.

Thanks again for your help.

That makes a lot of sense HR is more important.

If you already have a ANT+ cadence sensor you can look for one of the HR straps that has a ANT+ bluetooth bridge (if it is in your budget) , then you can use your ANT+ cadence sensor.

I have not used it but heard it works. https://www.dcrainmaker.com/2013/07/viiiiva-bluetooth-bridge.html


That’s not something I’ve considered , I will have a look.