Is it Possible?

Okay, so I've got this idea of a puzzle physics based game. There are 7 worlds and within the 7 worlds there are 25 levels. So that's 175 levels. Each level will be relatively dynamic with moving sprites and the objective is to reach the goal. I want to make this game available on all mobile platforms. So the question is: Is this possible with Construct 2? Would it run smoothly? How long would it take to make a game this big?

Why not? If you don't have restrictive conditions every tool is ok to be used. Plus C2 helps to test on many device types in little time (ex. with the Preview on LAN function).

(I'm talking as a C2 beginner, so here I could be wrong ) Referencing to so many platforms, the standard html5-jscript publishing mode is a nice & fast way to create and mantain the game. Being very dynamic and having the idea to use physic, you should dedicate time to test mobile performances (caring a lot to the mobile web browser used).

I think you should create one simple level for the mobile device you want to test to understand if the game looks cool (in terms of performance and use). Or you can create a complex one to see how it behaves in critical conditions

If every planet defines the levels solving mode as I understood, the time needed should be:

7 worlds (or solving modes) * 25 levels to create and test on the platform * platforms to test;

bye

Honestly yes its possible to make what your asking, but whether or not you can make it is a different question all together. Because of that we can not answer your other questions. The amount of time it would take and the quality of the game all depend on your skills not Construct 2 (or any other engines) capability's.

There is virtually no limit on the number of layout you create, if you have the proper license. (At least I think so)

I think that the time spent depend really on the overall design style you want to adopt.

For exemple a super simple, clean, and flat graphic direction will be way quicker to do than a complex, realistic one. I don't know if you're artistically skilled for that.

I would ask myself those questions:

-Do you want to use always the same sprite over and over like in Tetris or use a random generated level system? Basically, are you going to design each of those 175 levels one by one?

-How long is your time target? Are those levels like a Wario touch like? Couples of seconds for each, or like a longer time frame for each play which will imply to have a saving/password system.

I made a Pong-like game, and it run smoothly on every platform I tried. Including Android/IOS devices with touchscreen controls.

There is usually some method you can use to work around limitations, perhaps you might go for loading each level from JSON array data (in a text file within game data?) and have just one actual layout. Depending on the type of game (eg: if it's tiled) you can also re-use the same objects and save on the slowdown of destroying/creating objects all the time.

At the very least (if you go for one layout per level), write your events so that you can include the same event sheet on every level rather than making a new sheet and all that duplicate code. It seems mobile really takes time to optimize once your game gets some complexity.