Building an app like Instagram can be quite expensive. In fact, it may cost up to $250,000 or more.
First of all, you need a Dedicated App Development Team. This means you will need at least one iOS developer and one Android developer. You may also need a team that specializes in the server side. Depending on how complex your app is, you will also need designers, project managers and other support staff.
The cost of hiring these people is a key consideration, as is the fact that many developers require equity or stock options as payment, making them very expensive to acquire. The cost of building an app also includes things like software licenses and hosting costs, as well as testing and quality assurance costs. These costs can add up quickly.