Many people have asked whether Evernote Web, accessed from a desktop browser, counts as a “device” for Evernote Basic. It does not. You can access Evernote via the web browser from as many computers as you like, even on a Basic account. For more information about how devices are counted, please refer to our Devices FAQ.This means that you can access your Evernote account from as many computers or devices as you wish so long as you are doing it through a web browser and not from a downloaded app. So, if you have Evernote downloaded to your desktop and your phone you can then access it from your laptop by simply going to your browser (Chrome, FireFox, Explorer, or Safari to name a few) and type in www.evernote.com in the address bar. Voila! You are taken to Evernote where you can sign in using your username and password and you have full access to the web version.
If you want to maintain free access to Evernote (and why spend the $$$ if you don't have to), I would suggest that you download the app to the two devices where you use Evernote the most (for me that would be my Windows laptop and Android phone) and then access it via the web everywhere else (for me that would be from my Chromebook). Easy peasy and no extra expense.
Check the Devices FAQ if you have any other questions.