Uptasia is a free to play German browser-based strategy game by Upjers GmbH. It is only available in German language so far, and it is an interesting mix between the traditional city-building browser RTS and the "hidden object" genre of adventure games, in which players have to find well-hidden objects on hand-drawn backgrounds.
The game has two layers: a traditional social city-building like Travian, but without PvP, and the aforementioned hidden object game, in which players have to find hidden objects on various nice-looking and detailed backgrounds using their mouse cursor. This mode gives rewards in the form of money and other bonuses.
The game takes place in the 1800's, at the beginning of the Industrialism period, with the player's goal being to build a successful business empire. This includes constructing villages, exploring the surrounding world, inviting players to help and the hidden object mini-game.
The graphics are quite good, and the gameplay can be very interesting to play for short bursts, with the minigame having a 60 seconds limit to find as many objects as possible, and the ease of the management aspect. However, currently it is only recommended to play if you speak German.