The Apple iPad Air Wi-Fi 16 GB costs right now 529.50 EUR. The Acer C720-29552G01AII is 249 EUR, so you already saved 280.50 EUR by the purchase of the chromebook.
In order to get the ipad upgraded to a chromebook hardware you need to buy a keyboard, e.g. Logitech Ultrathin Keyboard Cover for iPad Air for 99.99 EUR, a Apple MD821ZM/A Lightning to USB Adapter a 29.99 EUR in order to get an USB port for digital camera cable connection or USB DAC connections, Apple MD822ZM/A Lightning to SD card reader for 34.18 EUR additionally if you want to access SD-Cards. If you need the HDMI video output (built into most chromebooks), with the Apple MD826ZM/A Lightning to Digital AV Adapter another 41.99 EUR are gone.
The chromebook comes with additional storage capacity at googles gdrive. To upgrade the storage capacity on the gdrive with an ipad, the gdrive price plan tells us to pay 4.99 USD per month. The gdrive chromebook offer is valid for 2 years, so 119.76 USD or 87 EUR you get as a gift by purchasing the chromebook.
So, in summary you save with the purchase of the Acer C720
- 280.50 EUR by the naked hardware
- 206.15 EUR for a keyboard, adapters which already come with the Acer C720
- 87.00 EUR you saved by the included free 100 GB of gdrive storage
In total you pay 822.65 EUR for the ipad with all the needed accessories. The ipad costs >3 times more!
Awesome purchase the chromebook!
BTW, there is even more to save. Music stream services like www.deezer.com or www.spotify.com do not charge the chromebook as mobile device. Ipads are (as iphones) are in the mobile devices category and you need to get a premium account to use the services there.