Super easy and useful. Just click the camel icon in the URL bar and you instantly see the price history charts for Amazon and third party sellers. You can also gauge how long the item has been available by how far the charts go back.

Doesn't work anymore.

Does not work on Firefox and amazon.ca

Not working properly needs to be updated

Now that it's been updated to actually support Amazon AU, it's smooth sailing.

cannot see it on firefox and amazon au. can the developer fix it. do not want to use google.

Does not work on Amazon AU

Firefox add-on has been abandoned in favour of Google Chrome extension. As a result, doesn't work on Amazon Australia. Shameful behaviour, ditching the open web and choosing Google's ecosystem.

Brilliant tool - saves me hours and hours of checking prices...

The tool itself works fine.
However, Firefox doesn't show me a captcha anymore.
I deactivated all extensions one after the other and found this extension as the source of the error.
Previously, cookies were deleted and cache emptied.

I am not getting the Firefox problems others are reporting (I am UK) and find this extension incredibly useful. Even if it does collect data on what you're interested in it will not be any more than all the other sites you go to anyway so if it saves me money (and it has) it's well worth it.
I really like that for 3rd parties it includes postage in the calculation (unlike other similar sites or plugins). My only reason for dropping a star is not being able to take UK Amazon wishlists automatically like it can US ones and it's a long process (unless I'm missing something) to go through and remove the tracking once you've bought the item.