CareUEyes is a shareware, i.e.you can test this fully function demo version for one month, after this trial period you must register,  but you can share it to your friends for get more trial days, It only takes 2 steps:

step1. Share your private invitation link to your friends.

step2. Your friend downloaded and installed CareUEyes from your invite link, and you will immediately get a 30-day extended trial.

Tips: During the trial period, the CareUEyes function is the same as the registered version, there will be no restrictions.
 
This is your invite link: https://care-eyes.com/