Research Development is how you keep your revenue afloat. There are two types of R&D, internal and external.
Internal R&D requires you to work on your product’s extensions within the company, communicate with your customers and keep an eye in your competitors, tackle what is out there and how you can improve, use this guide to structure your R&D budget and targets.
External R&D is for acquiring product and service extensions, it could even be cheaper both in money and time and it links you to a company that has the features you are lacking, this is a great example of how it should work. Find out what works best for you, Internal R&D works great for cross-sell and/or up-sell, while External R&D works great to cross-sell to old and new users.