Other applications you should are Evernote and Microsoft's OneNote. Both can function in stand-alone as well as syncing across platforms. Keep's advantage is that your Google login is also your Keep login. OneNote login is persistent as it is your Outlook.com or live.com login. I have found syncing OneNote at work to be problemmatic as that installation of OneNote insists on authenticating with Active Directory (AD). I haven't spent the effort to overcome that speed bump as Keep does the same with out AD. Evernote login was also a chronic speed bump making synchronizing was a hassle.

In addition to Keep, other applications you should consider are Evernote and Microsoft's OneNote. 

Both Evernote and OneNote can function in stand-alone as well as syncing across platforms. Keep's advantage is that your Google login is also your Keep login. OneNote login is persistent as it is your Outlook.com or live.com login. I have found syncing OneNote at work to be problemmatic as that installation of OneNote insists on authenticating with Active Directory (AD). I haven't spent the effort to overcome that speed bump as Keep does the same with out AD. So I use Keep for notes I need for work. However, I like to separate my personal data from my work data (a lesson that Hilary Clinton has learned the hard way). Thus the inability to synch OneNote at work is a blessing as it reduces the likelihood of spillage of personal data into my employer's systems. Evernote login was also a chronic speed bump making synchronizing was a hassle.