I have flyskyhy on my iPhone which records everything, but as a "newbie" myself i did not want to be letting go of the brakes every few mins to see what my height was, so I bought a Fairhaven Micro Alti. Not sure on the rules on advertising on here so won't say where I got it other that to say my instructor got it for me. They are a around £118 I think.
Its a great bit of kit, simple to use, I have it strapped to my wrist so I can see it at all times. Although I did have to buy a longer velcro strap to go over my winter suit. but that was only 3 quid.