The first principle is to plan and design applications taking into account the total uniqueness of mobile user experience. Although it is technically possible to develop a single application for usage on the web, on all mobile phones, smartphones and tablets, such app will not work well enough to become really popular. It is not possible to recreate the same experience on such different devices as smartphones, tablets and desktops, no matter how skillful android app developers are. There are many critical differences even between visiting the same website from a desktop PC and from a tablet, even in the same kind of browser.
Marketing researches tell us about rather big differences in how people normally use various devices and applications, and this difference must be taken into consideration. You cannot have all in one and save on costs, because it will not bring you the same many new customers, as separate applications for iOS, Android, desktop browsers and tablets would do. The worst case scenario is losing many loyal customers because they just don't like your website any more. From the other hand, custom software development of several new applications will cost a fortune even if outsourced. It is better to explore these new channels one by one, for example, starting from web software development or android programming and trying new ways after some rounds of testing and market research.
The second principle is to be flexible and not to expect too much from one single sales channel. Some startups and emerging companies focus on mobile experience of their customers and leave behind the traditional web experience. Such strategy may appear profitable if it serves the needs of a very specific, mobile-oriented business with rather strictly defined aims, like last minute hotel reservation. In most cases, custom development of mobile software follows more general aims like better brand recognition or expanding the audience on the cost of younger mobile users. Some companies want their own android application for the sole reason that it is in fashion, and then expect it to boost their sales no matter how efficient their overall business is. But professional android app development is very resource-demanding, so the company must adjust its whole business model before going mobile to avoid useless expenses.
Finally, as in many other cases, simplicity is the key. Users normally don't spend too much time with android applications they can't understand. Naturally, creative design is a huge competitive advantage - unless it makes the purpose of application unclear.
