I recently purchased an Epson ES-300W.
After some research found this one to fit the bill for a Mobile Scanner
Here is why:
I got tired of driving home to do scan backs after an appt when I could have taken another appt.
This unit has an internal battery and internal wifi to connect to the android or iOS Epson smartphone app.
It is very small and folds up into a box shape.
When needed, I open it, power on, launch my phone app, initiate the scanner wifi and connect to my phone, scan the docs to my phone thru the Epson Smartphone app, disconnect the scanner wifi, upload or email the scanned docs, power down the scanner and off to my next appt.
No wires needed (except to charge the internal battery). The scanner can be connected to computer if needed but I wanted a wireless solution to use in my car for scanbacks while out on appointments without the need for a laptop or tablet.
This one works great. Better than I expected. Saves much time and the scanner is very fast in
black and white mode (does color too). Has 25 page auto doc feeder.
Hope this helps.