It's been a while since I was in the business of A/B testing on my landing pages (~ 3 years). Back then I mainly used Unbounce. What is everyone using now? Unbounce back then wasn't so great for mobile traffic, and it still seems to be the case , so would appreciate some suggestions!
Google Optimize is free, Optimizely has a free feature flagging API feature as well!
I personally don’t like GO as it comes with a lot of limitation. But I totally understand why people use it. It’s great for super simple AB Testing, but it doesn’t work if you want to scale and do complex CRO. Another downside for me is you need to use Google Analytics.
Optimizely starts at 50k per year.
Affordable alternatives are VWO, AB Tasty, Convert or Kameleoon. (800-2000k per month)
If you have some coding skills (JS, CSS) you can take a look at my tool. I am offering a free plan with 10,000 tested users monthly. Early beta starts next month. Let me know if you have any further questions. :)
Have you tried Google Optimize? Its free and when it comes to simple test it is super easy and effective!