Hey, I had couple of questions regarding making mobile applications.My first question is that how much would it cost to make a social media/messaging app like a Viber/ Line / Whatsapp?
Second Question- If I want to raise money for my application, what is the best possible way to approach investors?
Putting aside for a moment that the messaging market is pretty flooded with many competitors and that your app offering would need some unique differentiator (or an amazing marketing/PR strategy)... your questions that can be answered in a variety of ways depending on details you have yet to share. But speaking broadly:
Mobile app development costs vary depending on a couple of things:
1. Functionality (how little, how much)
2. Integrations (OS and external)
3. Backend / server-side hosting components.
4. Depth of testing and iteration.
You also have to realize that building an app and maintaining an app are two different costs.
You need to find an app developer or partner and define the above before you will have the costs you are looking for. Generally speaking the initial development costs could range from 50-150k (or more) depending on the developer/partner and the above variables. Before going all out and build a full feature app, you should consider looking at the base functionality and build a MVP
Building an MVP could cost as little as finding a solid app developer and paying them for their time.
With an MVP, a good business plan, and some solid market data you would be better armed to start the hunt for funding.
Both of these are very loaded questions that are hard to answer in short form. For any software product or app you really need to go through a specification process before any development shop or developer is going to quote you (at least the good ones). One of my various gigs is specifically doing this and I've help all kinds of founders get through the spec processes. That alone will cost you between $1,000 and $5,000 in my experience depending on the scope needed and the skills of your spec developer. However, the cost of the dev project will drop at least that much in my experience because of the communication and expectations going more smoothly, so I think it's worth it.
With respect to fundraising from investors you are going to have to go through a full business model development process which may or may not include revenue planning. You definitely need someone to help you through this because it's not a short answer.