What are some alternatives?
When comparing Crystal and 1Blocker, you can also consider the following products
BlockBear - Block ads and protect your privacy on iOS with a bear
Adblock Plus - AdBlock Plus is a browser extension for Firefox, Chrome, Opera, and several other popular browsers that prevents intrusive ads like pop-ups and malicious code from appearing on websites you visit.
StopAd PRO - The ultimate ad blocker for Windows and Mac.
Ghostery - Privacy tool for transparency and control
Goodly - Student loan repayment as a employer benefit
Adguard - This includes video ads, ads in your favorite apps, games and on any website you can imagine. Dozens of ad filters are available to you and are updated on a regular basis, guaranteeing the highest filtering quality.