App suggestion for low-friction way to log regular text entries?
Whilst not being the intended purpose, the app "Day One" which is available on iOS and Mac OS is a journal/diary program that is focussed on hassle free text entry.  It will sit in the menu bar on Mac OS X, and you can configure reminders for how often you would like to enter something.  Th eexpection is more along the lines of twice a day etc, but you can tell it as many times as you want/need.

When the reminder is due, it will produce a small popup box under the menu bar icon that allows you to type a few words in (Markdown supported, but no fancy formatting toolbars etc) and then save them, you can postpone or ignore entries if you like.



It will collate all your entries together, sync them between other instances inc. the iOS app via Dropbox or iCloud, and you are then able to  search for entries specifically, or list by day/month/year all in a timeline style like a diary.  It won't do fancy stuff, like applying time or entries to specific codes etc, or produce reports and so on, but if you just need manuall adhoc review of contents it's a good fit.