Having an app created for the Apple or Android market can be very expensive. The prices are coming down as more and more companies opt to have one but costs can range from the low thousands up to hundreds of thousands depending on what the app needs to do. Certain businesses definitely benefit hugely from having apps, these are companies in industries such as Social Media, Clothing and Banking. These types of apps are being used every second and make simple tasks much easier. Many of us rely on our tablets or mobile phones as our only access to the internet, so it makes sense to have an app created to allow people to connect and interact with your company more easily.
For some companies, I don’t feel an app is particularly necessarily needed. It may give them a little bit more of a professional feel and allow them to interact with their customers a little easier, but often the initial cost is far to large to justify this.