So is walking across the road.......
There is always risk but if you bank with SCB and want to make payments online you unfortunately now have no choice other than to use their app. I don't like it and even had to buy a new phone because of it - otherwise becomes very inconvenient.
A well respected and occasional poster on here (sorry can't recall his exact posting name) works for Bangkok Bank currently in that area and he would probably disagree with you.
You may have the technical nouse to secure your pc and online behaviour but unfortunately many don't and for them, whether online on a pc or a phone, there is always a risk.