How much it costs to develop and sale an app/game?

It will help if you define the scope and genre of your game (e.g. similar to Flappy Bird, Mario Run, Clash Royale, etc.)

That said, you can probably find developers who will make A game for you for under $10k.

Someone with a professional quality threshold and a fair understanding of all the nuances of the industry (launch process, marketing, analytics, optimization etc.) will probably charge more for even a basic game. Without scope, it's hard to say. $25k-$50k.

If the game scope or detail are great, expect 6 to 7 figures.

If all of this sounds expensive, you can always teach yourself to develop games. The people who have the tenacity to do that often make the best games

 

https://www.otreva.com/calculator/

 

Something else: How much of your dream game do you actually have laid out already? Design documents, artstyle, mechanics, all that jazz.
If you need to hash all that stuff out first, that could be a few thousand as well, easily. If all you have is - quote - "some ideas", you are starting at -1 pretty much.

 

As indie dev, we estimate our work for about 70-100k usd for the latest projects. (www.yogamen.net)
The development of a similar one in "top" companies costs hundreds of thousands...
But it will be true game, not just one more soulless clone..

 

It all really depends and we'd need more information to get a feel for what the game is in order to make a better estimate.

 

As said above, it really depends on what you want in the game. If the scope is simple, and you later want to expand on it, it will increase the cost.

 

I can make Flappy Bird clone for USD1000.

 

Wow, way to dismiss the entirety of the mobile industry that doesn't have indie cred.

As others have said, development costs vary depending on the scope and depth of the project, the general labor costs of the geography where the team is located, what your post-launch support plan looks like, as well as marketing and user acquisition.

For a formal, established mobile studios, $10k USD per man month is a reasonable building block, though even that's getting a bit low for mobile studios in the US. It's obviously less for indies, low-cost geographies like India (even the UK thanks to Brexit), and studios with no track record.

Please note that the 10k isn't going directly to salary, it's a composite figure that takes into account the overhead (rent, powerbill, non-team specific managers, etc). When bidding projects many work-for-hire studios use a figure like that to calculate the cost once they estimate the number of resources required. That was actually part of my job when I was a dev director at a work-for-hire studio for many years.

If you want want your game to be visible in such a crowded market, consider spending just as much in marketing with an ongoing spend to offset customer churn, should sales warrant it.

Finally, and I say this with great love and respect: I hope your dream has a well-researched game design document behind it. Everyone has ideas, and ideas are not game designs. I can't tell you how many proposals I've heard that haven't thought beyond the "elevator pitch." "Wouldn't it be cool if you did a mashup of soccer and car racing?" doesn't result in Rocket League without a solid design behind it. If you don't have anything to offer around game mechanics and true system and level design, no one in their right mind is going to take on the project or fund it.