Cheaper than a budget smartphone, I would say pen and paper. And a mp3 player to listen to music.

I believe smartphones do a great job if you know how to use them well. The way you use your device is the best as possible.

I don't know if downgrading your phone to a long last battery "dumbphone", getting an old mp3 (or a sansa clip for example) and get an notebook with a calendar inside is a good idea. But... if you want, you can do this too.

I mean, if you do all of those things in a smartphone, and if you have no money issues to keep a device, and maybe pay the phone bill if you use it to call and receive calls. I see no point in reducing from the level you are now.

Books... It really depends on how much you read. If you read more than 3 books a month as I do, a basic kindle does an excellent job. In my country digital books are 20% cheaper than paper book (you don't have this in US as far as I know). If you read less than 3 books a month I would stay with paper books because the final price reduction on books to pay the device is not worth the depreciation time you will have the kindle.