[dritanm]

I have never sold (or bought) a web app before, but I have had to value various different types of assets due to my job. The most common valuation technique would be to use the Discounted Cash Flow model. In short, you project your pre-tax cash flow for say the next 10 years, and discount them at the required return which the investors are looking for. This rate is determined by a multitude of factors, such as the stability of your business model, target market, etc.

Then at the end of your projection, you simulate a sale of your business by 'capping' it at a certain rate. Then you add this terminal value to the sum of all the discounted cash flows calculated above, you have the total value for your business.

Of course in hi-tech sector things fluctuate too much too quickly. But the model should be the same, you just have to adjust your discount rate and terminal capitalization rate to account for those fluctuations.