How do I get my husband to keep his phone with him?

My husband was diagnosed with ADD last year, and started using alarms on his phone to keep himself on track.  It is much more successful than anything else he has tried and I'm grateful for that.  The problem is he's constantly setting his phone down and walking off.  Or forgetting to grab it in the morning.  So several times a day I hear (or an awakened by) an alarm that I have to hunt down in the house and deliver to him.  The first few times I didn't mind much - I figured it was the cost of having a more reliable partner - except now it's becoming a new unreliability and frankly, just making ME responsible for managing him again.  Sigh.

I appreciate the idea that I don't HAVE to do any of that - but the untended alarms are very disruptive to my life as I homeschool the kids while he works from home.  So ignoring it isn't really a viable option because it distracts the kids (who also have ADHD) and completely throws off my ability to do my job.

Any suggestions other than super-gluing his phone to his hand?