I’ve used other solutions like MarketPress before, but I think WooCommerce is by far the most beautiful, advanced and user friendly eCommerce solution for WordPress out there.
To keep the shops running smooth, I’m hosting all my sites on a VPS (Virtual private server) and using W3 Total Cache plugin as well to cache the pages and keep the loading speeds fast enough as well as reducing the strain on the server.
When I was first starting the Baros Records shop, I noticed that running both plugins (WooCommerce and W3 Total Cache) I couldn’t finish the checkout when using a mobile device, The “Proceed to checkout” button was simply greyed out, but it worked like a charm on my laptop.
To solve this issue I searched long time online until I finally stumbled upon this article which solved my problem instantly.
As soon as I added /shop* to Never cache the following pages: (in the menu Page Cache), the problem was gone!