This is the first update in quite a while! First, the timeline. I wore the watch daily from the time of my last update until roughly the end of the summer. Then, I accidentally hit my wrist against something and popped the acrylic screen protector free. When I took the watch fully apart to re-seat everything and glue the acrylic piece back in, I discovered that the PCB was significantly rusted and decided to take the opportunity to redesign the case. Then real life got hellishly busy and I did nothing until roughly mid-December. I started wearing the watch daily again some time in January, and haven't had any problems since. Some observations:

Enclosure

The biggest problem with the previous iteration was waterproofing. Since then, I redesigned the enclosure to use an annular snap-fit design instead of cantilevered tabs (check here for a better description than I could write). This means that it's a much tighter fit (it took some pressing in the vice to get everything properly snapped closed), but I've had no trouble with water getting into the watch since I made the change. I also floated a prototype case in a bowl of water overnight (with the snap joint below the waterline) and no water got in, so I'm reasonably confident that it's good enough for daily wear. The other possible point for water to get in is the button bar, so I increased the flange on the flexible TPU part and haven't had a problem.

Battery

There's still a problem that I haven't worked out with the MAX17262 fuel gauge that causes it to always report 35% battery or less, but empirical results don't lie: I'm getting 2.5-3 weeks of use on a single charge, which includes ample flashlight use. I'm pretty pleased with this; I sleep with the watch on, so I can't charge it overnight, but plugging it in for an hour every few weeks is a completely acceptable interruption to my daily routine as far as I'm concerned. I may even be able to extend the life further if I do some aggressive optimization, but I'm not certain it's worth the effort at this point.

Software

I still haven't made a lot of headway as far as the mobile app. Mostly I just haven't had the motivation; I don't actually need any smart watch features. I would like to be able to set the time automatically via my phone to account for RTC drift, but being a few seconds off every now and then is only slightly maddening.

Schematic

Now that I don't think the hardware is going to change much anymore, it seems like I don't have any more excuses to avoid cleaning up the schematic and posting it. I'll try to get that done in the next week or so. The software is also a mess, but I'll try to get that posted as well in case anyone is interested.

If you have questions, leave them in the comments and I'll do my best to answer them!