Why not just open the phones browser and do the speed test through the browser is my feeling, instead of another privacy breaking APP on a phone using resources.
But forget that above, using your phones browser you actually are testing the speed of which the phone can download and process/use the information>
So anyway, I just open my browser and do a search "speedtest" and then select one or two of the popular ones, run the test without downloading their app and I am done.