Since smartphones and tablets become more and more popular they frequently replace paper notebooks. It is also frequently happen than one person have several devices and it is very convenient to have all information available on all devices using synchronization via Internet.
There are a lot of services intended to solve this task. I will describe below criteria which I used to select service for my usage. I will also describe my experience of testing and using some of that services.
Apple also provides Notes application with synchronization support for free. But I will not describe it here because it is very simple and lack a lot of basic features.
I will not consider in this article how powerful text editors in that services, because notes usually requires basic formatting functionality only , which are supported by all mentioned services. SimpleNote is the only service which works with plain text and allow to use Markdown formatting.
Despite described products may evolve and change fast the described features below can be used during the choice in the future even if product changed significantly. Article could be helpful for you even if you consider a service not mention in this post. It can be used as a list of criteria.