As an end user and frequent buyer from online stores, personally, I don't think having an app for your store is a good thing since I do not shop at one shop wherein I may not be able to have all of it in one app. I would most likely download and use an app of Amazon or ebay wherein I can browse a lot of products from different sellers. But I do love a mobile friendly website of a personalized online shop. I would suggest you utilize the use of these e-stores and then have a link on your website so that shoppers can take a peek if they are interested in your products. Make use of all the top social medias too. If you can, advertise on Facebook too. for on early start up of on online store, you must put so much effort on getting known. It will be an added bonus that during the first few weeks of spreading information about your store, that you'll have a buyer. But do not expect too much from the start and vice versa. Do not be discouraged when you are not generating sales too.