Reading is probably the best single thing, but there are many other options or you could even combine several into an evening routine.

Other options:

• Short evening walk
• Hands-free call to someone like a family member, friend etc.
• Listening to music that is not too intense/energetic.
• Journaling or light writing that is not seen as "work".

I like to think about how I can set myself up for success the next day. Do things that I would have had to spend time and/or attention/stress on the next day anyway. That way, I don't feel like it is productivity wasted not doing anything that last hour, instead it is freeing up more time and attention the next day. So I may take a quick look around the apartment and tidy it up a bit, write a short list of items I need to remember doing first thing the next day as a to-do so that I don't have to begin the next day figuring that out, maybe even prepare the clothes, bag or gadgets that I will want to have prepared for the next morning in advance. Basically, prepare so that when I wake up I have no need to spend time or thought about anything else than heading out. Then I may read for whatever time still remains until I feel sleepy or complete a chapter.