If you download osmand you can use cycletravel's routes and osmand will give turn by turn directions.

Osmand is also a great backup planner as it works totally offline and plays well with other apps. 

It is a bit clunky and has a steep learning curve, though. It is a great asset for the bike tourer.

That's all ignoring the disadvantges of using a phone as a gps device. 

If all you want is a gps device to follow a route there are far cheaper options out there.

Thanks. I currently have a Garmin Edge Explore 820. It's been brilliant, but it's 5 years old now and the battery is starting to go. Also the one thing it wasn't good at was if you went off route it didn't really get you back. I'm looking at the new Garmin 1030+, big screen, big battery and re-routing function. But it is £500! Osmand looks an interesting option, but best option would be if Cycle Travel could do it!

Rerouting is not all it's cracked up to be. Depending on location, available routes and personal preferences it may not be terribly useful for you. Personally, I have the function disabled on my Wahoo unit. On my previous (non rerouting) unit I never missed the feature. Nor do I use turn by turn. 

Osmand works (with rerouting) so you have an immediate solution in advance of the cycletravel app. I know there's one in the pipeline but I've no idea what features it will offer.