I was hoping someone in the community might have already tried to download iPhoto to a MacBook and could let me know if it successfully loaded. My intention is to download my photos to the MacBook while in the field, to be viewed and then later transferred to my iMac.
Both applications - iPhoto '11, version 9.6.1 and Aperture 3.6 are working very well with MacOS X 10.10.3.
I am using them on two MacBook Pros and an iMac.
If iPhoto or Aperture are showing at the App Store in the Purchases tab, when you sign in with your AppleID, you will be able to install them from your Purchases tab, as Terence Devlin said in the first post.
You may need to unhide the purchases however: https://support.apple.com/en-us/HT202320
There are no guarantees how well Aperture and iPhoto will work, once you upgrade beyond Yosemite, when the next MacOS X will be released.
When you look for other apps to replace Aperture, check out Capture One Pro and compare it to Lightroom. For me, Capture One seems to be closer to Aperture than Lightroom.