Most of the apps that run on Chrome OS are web apps. In other words, shortcuts to webpages that do the work. There are a few that run outside of the Chrome browser, but most of the more powerful ones are web based. Extensions for the Chrome browser are the other tools that will help make the transition go more smoothly.
Once again in the second half of 2016, the entire Android Play Store will become available to Chrome OS. When that happens ever most of these suggestions won't be as necessary. Because there is a Photoshop app for Android. There are also better versions of Office on Android then on their Office web apps. It is something that will definitely need to be revisited once that happens.
This list of apps and extensions will be what I have found to be useful for teachers. I am sure that others will come out in comments later.
- Office 365 Mail Checker: a great extension if you are still locked into Outlook for emails. Notifies you with an email near the address bar and also one in the bottom tray. Chrome doesn't even need to be open to get the notification.
- Checker Plus for Gmail: if you happen to have Gmail as your main email, this is a must. Another extension that allows you to get email notifications and even respond without having to open up Gmail.
- Cloud Convert: one of the best all around file converters out there. If you don't like the way Google Drive's built in converter works, you can always try this one. I usually use it to convert pdfs to jpgs. Also integrates well with Google Drive.
- Pixlr: Doesn't need an introduction probably if you have researched Chromebooks before. Pixlr is a solid photo editor. It's not Photoshop, but if you need Photoshop on a regular basis you won't be buying a Chromebook.
- Nimbus Screenshot: taking screenshots of pages is very important for educators. This used to belong to Snagit, but they are discontinuing their Chrome extension, but this one is just as good. Another good screenshot extension is Fireshot. I actually use them interchangeably.
- Save to Google Drive: an unknown extension that is a must when you transfer into Chrome OS. This extension allows you to save any page, picture, or document directly to your Google Drive with one click.
- Google Keep: This extension is useful if you have started using Google Keep. Similar to some of the other extensions like Share to Classroom or Save to Google Drive, this app takes any webpage that you are on and shares it to Google Keep. This is useful because if you are putting together resources for students, but want to look at them in more detail later, you can save them to Keep and have them waiting for you at a later time.
- Share to Classroom: For teachers using Google Classroom, this extension adds a share button. When you see a website you want to share, just click it and it will go to the class you want to share it with.
- Office Editing for Docs, Sheets, & Slides: This is another must. This extension allows you to edit Office documents in Google Drive. Enough said.
- PDF Escape: In a perfect world, pdfs would be naturally editable, but they aren't. If you were to search PDF editors on the chrome web store, most aren't that highly rated. It is difficult to edit a pdf file. PDF Escape is an app that does a very good job of allowing you to open and edit directly into the pdf and save it. There are a ton of PDF apps out there and this is probably my favorite.
- HP Print for Chrome: talked about this in the printing post. A must if you have an HP printer.
Those are some of my must have apps to help make that transition from Windows to Chrome OS a lot smoother. If you have any other apps you want to share go ahead and list them below.