For simple, single page notes you can try simplenote [0]. It has nice Mac, Linux, iOS, Android clients, tagging and markdown support, and instant sync on official clients. It's also free. I use it for non-sensitive fast notes like a reminder notebook.

Also, applications/cliens like nvALT, nvPY provide a very very fast workflow for instinctive note taking and recalling.

[0]: https://simplenote.com