Q: What is a good OS to upgrade to for my Macbook Pro early 2011 edition? I currently have Snow Leopard and I am really happy with its speWhat newer OS won't be sluggish on my early 2011 MBP?

In order to use iCloud your Mac must be running Yoosemite. Your Mac meets v10 Yosemite requirements > System requirements for iCloud - Apple Support

How to install OS X Yosemite on your Mac

Yosemite is free and available for download from the App Store.

If you are using Rosetta on v10.6 Snow Leopard read prior to upgrading >  Upgrading to 10.7 and above, don't forget Rosetta! | Apple Support Communities

Make sure your Mac has plenty of available disk space. Right or control click the MacintoshHD icon on your Desktop then click Get Info. You will see Available and Capacity in the Get Info panel. Make sure there's at least 15% free disk space.

Be aware any third party apps you may have installed that are compatible with v10.6 Snow Leopard may not be compatible with v10 Yosemite.

You most likely have 8GB of Ram. That should be more than enough. 4GB is officially enough but it could be a bit low. Try it out.

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