The issue is, you should never be granted obvious patents like "swipe to unlock".
Mobile phones / tablets are fairly trivial by now. Computer, touchscreen, software. It's not rocket science. Nothing there should really be patentable IMHO.
Your example is very apt. Isn't it great that you can't patent mathematics? Software and hardware should not be patentable like it currently is.
Sorry, but since I can remember, (20 years ago say), the idea of a touchscreen tablet/smartphone was obvious. It was absolutely inevitable, and it was boring waiting for the technology to appear to allow it to happen. Absolutely nothing on any smartphone, tablet, etc is innovative to the point where a patent should be granted.
The devil is always in the details. Since the first internal combustion engine, the car was an obvious development. But it turns out that there is more subtlety to making a car than simply swapping a horse for a motor on a carriage. Would you say that absolutely nothing in any car or truck is innovative to the point where a patent should be granted?
Tablets are an interesting case study because we've been down this road before (google for Windows XP Tablet Edition, 2001). Anything in a modern tablet that wasn't in XP Tablet, or the Apple Newton, you can say required innovation to do.
Then I hope you never need to do anything more complex than copying something someone's already done, least of all invest your own money in risky research that may yield no results.
The only area I think patents do make some sense is for medicine, where the R&D costs are astronomically high. But most other fields, R&D isn't that big a cost.
The thing is that it just isn't that obvious.
Not one cell before Apple's iPhone had swipe to unlock. Not one cell had touchscreen that works without stylus.
Same thing with tablets. Sure, Microsoft started making them long time ago but using styluses on the same GUI was not that practical. That's why they never entered mainstream market.
iPhones and then iPads brought new GUI for whom you didn't have to use styluses and you didn't have tiny unclickable icons. Everything is made for touching from the ground up.
Not one cell had touchscreen that works without stylus.
Incorrect: LG Prada.
For me, pointing to one or two features of the iPhone as proof of it being innovative misses the target. I regard Apple products as innovative and successful principally because they are consistently usable, designed well, marketed well and technically innovative at the same time. Apple's competitors rarely hit all those targets in a given product.
Mobile phones / tablets are fairly trivial by now. Computer, touchscreen, software. It's not rocket science. Nothing there should really be patentable IMHO.