If it's a sale with a video feed it's harder on either the phone or computer as there is just a lot more bandwidth that needs to be handled. If you have a good WiFi connection it will probably be more likely. First sale we tried to bid on via our phone we ended up not getting a strong enough signal and our bids never went through. When I've had a good signal it can work.
The online sales that don't have a real sale going on are not a problem but in the MWSRS case I presume the video will be connected. You could always resort to a back up plan of having someone there bid for you while you talked to them on a phone. Get your bidder number ahead of time and if you can't keep up watching an earlier sale have an person there bid for you.
