If you are planning to start an e-commerce dropping store offering the products like posters, T-shirts, mugs, books and other customized products, but preparing resources to fulfill these are not that easy, and relying on print-on-demand apps on Shopify App Store is the way to go.
Printful

Printful – top-rated print-on-demand service
Printful is one of the incredibly print-on-demand powerful apps on Shopify App Store. You can discover thousands of products from T-shirts, phone cases, pillows or many more. The outstanding features of Printful are:
Shipping: on average, within two to five working days, the products will be available and ready to be delivered to the US, Europe and Mexico and it takes about three or four days additionally to ship products to selected destinations. Shipping costs are from $3.99.
SPOD

SPOD allows you to customize design
SPOD is highly appraised for its rapid fulfillment times – 95% within two days with very competitive prices.
Teelaunch

Teelanch turns your ideas into reality
Powering over 165,000 Shopify stores, Teelaunch is an amazing print-on-demand app to start your e-commerce business.
Offering the highest level of product quality at a competitive price. Wide range of products – about 120 items, from T-shirt to phone case, journals, jewelry and hundreds more.
Printify

Printify - a huge line of products
In fact, Printify is a vendor, so you have a better chance to discover the huge network of worldwide printing partners. However, the product price, shipping cost, delivery periods or packaging will be decided by the real provider.
Lulu xPress

Lulu xPress - perfect option for creatives
In charge of printing over 5.3 billion pages all around the world, Lulu is the pioneer in printing books on demand. Lulu xPress is designed to integrate with your Shopify store, when your store gets an order, it will be sent automatically to Lulu network, Lulu will print and deliver directly to the customers.
Various book designs, common and uncommon ones, customizable size, color, binding and cover options.
3,000 combinations of bindings, layouts and prints, appropriate for magazines, textbooks, catalogs and even calendar, etc.
We have rounded up the 5-best print-on-demand companies that you can trust to cooperate and flourish your dropship business. Most POD apps on Shopify store are equipped with an auto-order process, design customizable functions, compliance with order specifications, punctual shipping time as well as logo attachment. Each company has its own merits and drawbacks, keep in mind to thoroughly review their shipping, product catalogs, printing options as well as additional features which set them apart from the others before selecting.