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I've used Phaser which has a useable editor now. It's close to Construct, but I think you won't find somethink that is really like Construct at the moment. At least I don't know something similar.
More complex but still easy to use is Cocos:
Another free and simple to use engine is Panda. But is has no editor and you have to do everything by code:
For codeless projects you can have a look at Scratch:
Or on Android and iOS have a look at PocketCode:
One more thing:
I haven't tried, but it seems to be similar to the concept of Construct