Shopify guides

How-to guides and side-by-side app comparisons for Shopify merchants. We build some of the apps we compare, and we say so at the top of each page. Prices and limits are copied from the public App Store listings, with links so you can check them.

How-to

How to add custom CSS to Shopify (2026): every option compared

Four ways to add custom CSS to a Shopify theme, with the built-in field's 1500 character limit explained and the free apps compared side by side.

 Comparison

The best free age verification apps for Shopify (2026)

Six Shopify age verification apps compared on what their free plans really include, with prices, limits and features from each App Store listing.

 Comparison

Cart Bump vs Axe Checkbox Upsell: which order bump fits your store?

Product page checkbox, cart page offer or checkout bump? Cart Bump, Axe, BumpPro and OrderBump compared on price, placement and plan limits.

App help

Setup steps, every setting explained and troubleshooting for each of our apps.