The majority of the hidden object games on iWin.com are available for play via a paid download, though many also offer a limited free trail. The sites does offer some hidden object games to play online for free via its Online Games section under the Puzzle Games category.
To access the free online hidden objects games, you need to visit the Online Games section of the site, as of 2015. This area includes several featured games as well as options to browse games based on categories. As it does not offer a section specifically dedicated to hidden objects games, you need to browse through the puzzle games in order to find them. Some games, such as "Hidden Object Daily," include the relevant term in the title, making it easy to identify them. Others don't mention the type of game in the title, which means it's necessary to visit the individual game page in order to read a description of its mechanics.
The gameplay for the different hidden object games follows the basic structure of clicking on different items from a level-specific list. Most levels include various trick objects meant to distract you from your search for the specified list. Some games also include features such as time limits and bonus items that disappear after a certain period of time.