A close rival of Evernote, Simplenote offers many of the same kinds of features, but limited to iOS devices and the Web. Unlike the others, Simplenote's free service comes with ads. A premium version without ads and extra features like synching with Dropbox, the online storage service, is $20 annually. In a sign of how hot the note-taking field is, Automattic, the company behind WordPress blogging software, acquired Simplenote's parent earlier this year.
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