AtTask is a web based project management solution that comes with some professional service automation tools. At $30-$60 per user per month, it is one of the most expensive offerings on the market, but AtTask has a lot of features to justify the price and most AtTask reviews are quite positive. Unlike most project management solutions, AtTask is available both in cloud and on-premise. If you are looking for a free AtTask alternative, the one available both in cloud and as self-hosted software with source code access, take a look at Bitrix24.
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