Go with Hotjar or Clicktale, they're the best in the business. You've got to keep in mind that heatmaps will always be a sample of a population. Unless you're paying a massive premium they aren't tracking literally every click on a page.
Heatmaps are pretty useless on their own, but paired with digital analytics, user research, etc they can provide some serious value.
For example, let's say you've got a massive visitor drop-off on your shipping details page and you're trying to figure out why. Heatmaps are a great way to contextualize the problem. You'd be able to see A.) Which form fields are being clicked least often B.) where people stop scrolling on a page (if your program has scroll tracking) C.) If users are clicking off the page to go do other things.
You can do a lot with that information like:
Run an AB Test that reduces the amount of form fields to the screen depth most visitors reach
Remove the form fields that are filled in the least (removing major barriers)
Check your analytics to figure out how often visitors who click certain links from the shipping page go on to buy. If you find a particular link leads to less conversions on average, test removing it from the page completely.
These are just a few example of heat maps. I like integrating them with my AB Testing program and looking at the different ways users interact with content depending on changes in page layouts. You can gain some real insight here.
For instance, let's say I wanted to test whether a navigation with 10 options would convert more users than one with 5. So I run a test and the 5 options wins. Great. But what if it turns out that even though it lost, a very large number of people were clicking a certain part of the navigation in option 10 not included in option 5. Heatmaps would let me see that. Then I could run another test where I included the highly clicked menu button and one where I exclude it.
Good heatmapping programs also come with scroll tracking and use recording sessions as well. All very useful tools in analyzing how people interact with your website.
