Does my Pro account cover 2 computers and a mobile phone?
A CCleaner Pro licence/subscription is for 1 device.
A CCleaner Pro Plus licence/subscription covers 3 devices any mix of PC, Mac, and Android.
A CCleaner Premium licence/subscription covers 5 devices any mix of PC, Mac, and Android.
If your phone is an iPhone then the CCleaner for iPhone is not covered by the multi-device licences and you have to purchase it seperately from the Apple Store.