Currently considering a new device for artwork

So recently, I've been having trouble with finding time to finish artwork. I Have a desktop at home, but other than that, if I have to draw something outside of home (Say I wanted to draw commissions between classes), I would normally be limited to only drawing on a clipboard, and if I ran out of paper, then drawing is out of the question. The point is I am not on my desktop as often as I used to, and I am thinking of getting a device to draw on so that if I have to go somewhere, I can finish commissions on the spot if I need to. Since I'm usually not home as often due to classes, I would love to spend the summer saving up for either an iPad Pro or a Microsoft Surface Pro 4 so that I am more prepared for the next semester.

For how I will save up money, I might be doing more commissions this summer, but I'm also going to make a sequence with a ten page story that may be for sale. The sequence will have a cover, 12 pages, and the 10 page story I mentioned, so I guess I'd price it at around 7 dollars if I were to sell it. I may also consider doing another donation sequence once I get the last one finished, but that is a maybe. I just want to know if anybody would be interested in ordering a commission from me in the future, and if so, here is my deviantart profile: http://berry-duke96.deviantart.com/ my forte is inflation art, but I like to draw quite a bit of things. Just contact me and tell me what you want and how you want it, and we can discuss from there, and I will share my PayPal information as well. 

For my schedule, it should clear up May 3rd. I will start to livestream on Picarto every Friday at 3pm Eastern Standard time, and I tend to do request sketches at the end if I get 3 to 5 commissions that week. Finally, if anybody is curious about how much I am saving, I am currently going to save up a minimum of $1100. That is enough for me to afford a portable art/note taking device. Any questions or concerns are appreciated, and thanks for reading.