best shopify apps in 2021

Updated: January 26, 2022

Speed Boostr is a Shopify optimization and development agency, but we also have a ton of collective experience working with Shopify stores and apps. This is our curated list of the best Shopify apps we use and like in key categories.

This is not an open directory and we don’t accept paid placement. We only include apps we trust, use, and would recommend to our community, friends, and fam.


These apps are all proven positive ROI generators, boosting sales and saving time. Scroll down to see the key features and descriptions of each app.

Quick links to get the best apps


Performance optimization helps increase SEO, engagement, traffic, and conversion rate. Conversion rate optimization increases the value of your inbound traffic.

Crush Pics

image optimization app Crush Pics automatically compresses your website images to make your site load faster.

Key Features:

  • Automatically compresses your product, asset, collection, and featured article images
  • No quality loss if you choose “lossless” compression
  • Faster website = higher conversions, SEO rankings, engagement, traffic, and revenue
Crush Pics is a quick win to make your site faster, improve your SEO rankings, and increase engagement and conversion rate. Images are generally the heaviest part of a web page. You can manually compress them (boring), or you can just install Crush Pics to automatically handle it for you (and any future images you upload). There’s a free version, but for most stores it’s worth it go with a paid plan ($5/mo) to compress more images automatically.

Bonus feature: You can also mass update your image “alt” attributes and file names to make them more SEO friendly (available on paid plans).

A faster website improves most of your key metrics, so investing in improving your speed is an easy positive ROI. If you want a tutorial for setting this up, check out our Shopify image optimization guide. Price: Free – $19.99/mo
Get Crush Pics here

File Optimizer

file optimizer Shopify app File Optimizer gives you the opportunity to optimize theme files in your store without any developer experience or knowledge required.

Key Features:

  • Help improve your site’s load speed by compressing files to load them faster
  • Minify CSS, JS, and Liquid files
  • No coding experience needed
If you get warnings for file minification in tools like the Shopify Analyzer or Google PageSpeed Insights, this app will help you clear those warnings. Minifying website files is a core component of performance optimization, this app helps you do it without needing a developer. Bonus for Shopify sites: this app minifies Liquid files, which are difficult and time consuming to manually minify otherwise. A faster website improves most of your key metrics, so investing in performance is a solid investment in your business. Price: Free to try, $24.99 1 time charge for unlimited access
Get File Optimizer here

AMP by Shop Sheriff

best shopify google amp app - shop sheriff AMP (Accelerated Mobile Pages) is a Google backed project that makes mobile pages load faster. When your pages are formatted with AMP’s code guidelines, they get cached by Google servers and pre-load during search results. This makes your mobile pages load instantly from Google search. AMP by Shop Sheriff automates this process and has a visual editor to customize your pages.

Key Features:

  • Instant loading mobile pages
  • Lightning bolt badge in mobile Google search results
  • Studies show increase in SEO, engagement, and conversions
Read our in depth guide here: Shopify AMP Guide. The app is pretty easy to set up, has a free trial, and doesn’t modify your existing theme/pages, so feel free to check it out and experiment. Price: Free – $29.99/mo (also has an Enterprise plan)
Get AMP here

Theme Scientist

Theme Scientist shopify best AB testing app Theme Scientist is an easy to use A/B testing app for Shopify stores.

Key Features:

  • A/B test 2 themes with different colors, features, content
  • A/B test product attributes
  • Analytics: Get stats on your tests to see which version wins
  • Schedule a theme to publish at a specific time in the future
Free trial: 14 days Price: Free – $29.99 / mo
Get Theme Scientist here


Automation is probably my favorite topic in ecommerce marketing. There’s a beauty in setting up a good foundation and generating automated sales forever.


klaviyo best email marketing app in shopify app store Klaviyo focuses on smart email automated marketing for eCommerce stores.

Key Features:

  • Amazing automated flows, templates, and segmenting
  • Insane amounts of analytics and data tracking
  • Easy to use, and lots of pre-set flows to setup
Here’s a guide / case study we did on Klaviyo: automated email marketing with Klaviyo. If you like automated marketing, you’ll love Klaviyo. The ease of segmenting and automation is incredible. Multi-sequence abandoned cart emails are nice (and included), but what’s really cool are things like advanced tagging and segmenting for delivering specific email sequences to customers that purchased specific products or from specific collections (great for cross selling). You can send re-engagement campaigns too… example “If customer purchased something in the last year but hasn’t purchased (or visited site, opened email, etc) in the last 6 months, send a special offer”. Those are rough examples. If you want help setting up detailed flows like this, we can help you out just give us a shout.

Price: Free – scales up based on subscriber numbers

*It’s more expensive than other email apps I’ve used, but if you set up the automated flows you should have no problem stacking a nice ROI.
Get Klaviyo here

Klickly – Automated inbound traffic

Klickly easy traffic generator Klickly might be my favorite inbound traffic app… and it’s free! It’s like having a PPC manager steadily creating ads, but with no ad spend and you only pay a commission on conversions like referral marketing. Nice!

Key Features:

  • Commission based ads (no app fee, no ad spend)
  • Runs on autopilot
  • Guaranteed +ROI for any sized business
We’ve experimented with Klickly, here’s a 30 day snapshot, getting 3K clicks in a month and generating a 3.6 ROAS. Price: commission based
Get Klickly here

At time of writing Klickly is only available for USA advertising, but that may change as they expand.


Get people interacting more with your site and closer to making a purchase. Increased engagement and page views also helps your SEO.

Covet Pics

Covet Pics is an Instagram and shoppable gallery app for your Shopify store. It’s also powerful enough to automatically show Instagram images from your customers on your product pages.

Key Features:

  • Automatically pull in Instagram feeds into a cool widget
  • Product tagging and shoppable Instagram widgets
  • Add social proof by showing customer pics with your products

An A/B test study from Taktical Growth Hacks showed that product pages with customer Instagram photos showed a 24% increase in people reaching checkout.

Covet Pics is the easiest way to set up customer IG photos on your product pages. To see our full guide on Covet Pics, you can read our Best Instagram App for Shopify post. Price: Free – $49.99/mo
Get Covet Pics here

Smile Rewards & Loyalty Program

This powerful yet easy to use rewards program app generates more repeat customers, brand loyalty, and customer referrals. It also has over 3,000 reviews in the Shopify app store. Shopify rewards app by Smile

Key Features:

  • Easy to setup rewards and referrals program, runs on autopilot
  • Create engagement actions to earn points and rewards (discounts, free shipping)
  • Create VIP tiers to encourage brand loyalty and give special bonuses

Examples of how customers can earn points (these are customizable):

  • Signing up for the program
  • Follow your Instagram and Facebook, share on Facebook
  • Review a product
  • Celebrate a birthday 🎉
  • Refer a friend (both friend and referrer get discount)
Side Bonus #1: Capturing more first time visitors. When you have Smile, it creates an icon on your site that people can click to see a popup of your rewards program. Set it so people earn points by signing up and you’ll captured new potential customers (and email address) that are interested in your brand. Side Bonus #2: Be a cool brand. Creating more engagement, rewarding your loyal customers, and providing referral incentives all strengthen your brand’s community. Price: Free – $199/mo (also has Enterprise plan)
Get Smile here


People like seeing other people using your product. Social proof is a great way to increase your conversions while building community around your brand. is the best reviews app on the market. It’s packed with features, built with performance in mind, and easy to set up automated systems.

This is a must have app for every Shopify store.

Key Features:

  • Automatic review requests, featured review carousels, social sharing
  • Engagement features like questions, discount incentives, picture uploads
  • Includes SEO rich snippets so your ratings show up in Google search results
Judge.Me has too many features to list – it’s a super powerful reviews+ app that increases engagement and breathes life into your store with reviews and questions/answer features. I’ve personally been watching this app grow over the last few years from a small reviews app to a feature-packed, speed optimized, well designed go-to Shopify app. It’s insanely low priced, has great support, and you can easily import reviews from anywhere. Price: Free – $15/mo
Get Judge.Me here


Refersion is an easy to set up full-featured affiliate marketing platform. Referral programs give you social proof, backlinks (great for SEO), and no-risk referral traffic. They also build community by connecting with people that vibe with your brand.

Key Features:

  • Create an army of affiliates promoting your brand and linking to your website
  • Create unique discount codes for affiliate promotion without links (for Instagram influencers, for example)
  • Analytics and dashboard software for you and your affiliates
Set up an affiliate program easily with Refersion, then start connecting with affiliates that vibe with your brand and products to create an automated inbound marketing channel. Price: $89/mo flat rate (unlimited affiliates and no % fees)
Get Refersion here

To further automate this, scroll to section 2 in this automated marketing strategy post to see how you can use Refersion with a VA to find influencers and shopping lists, then invite them to the program.

Tapfiliate is great too. Refersion and Tapfiliate are our go-to platforms for managing referral programs. Check them both out and see what works best for you. Contact us if you need help setting up.


These apps help run your store more efficiently behind the scenes + keep your business safe.


termly compliance solutions Termly helps keep your website compliant with data privacy laws like the GDPR, CCPA, cookie consent, etc. ⚠️ You must comply with data privacy laws if you have website visitors in countries with data privacy laws.

Key Features:

  • Easy to use policy generators (privacy policy, cookie policy, terms and conditions + more)
  • Termly stays up with laws and optionally updates the policy to stay compliant
  • The generators are more powerful than the default Shopify generators – a Q & A tool guides you through policy generation
  • Help protect your business from the growing number of data privacy laws you need to comply with
We use Termly on our site to stay compliant + recommend them for Shopify sites as well. See our Guide to Make Your Shopify Website Compliant with Data Privacy Laws for a step by step guide. Free for limited use. Price: $10 – $20/mo for all features
Get Termly here

Order Automator

Order Automator shopify app preview The Order Automator saves time and money by automating tasks like tagging and fulfillment.

Key Features:

  • Auto tag orders or customers based on order conditions
  • Auto fulfill line items by creating custom rules
  • Auto fulfill line items connected to 3rd party services, like Amazon FBA
  • Send email notifications based on order conditions
  • Get notifications on high risk orders, or auto cancel them
  • Order monitoring, for example notify staff of unfulfilled orders
Free trial: 7 days Price: $10/mo
Get Order Automator here


backup app for shopify - rewind Rewind is a key Shopify app for serious stores doing any volume. Your online store is the home base of your ecommerce business. Shopify backs up some things, but Rewind backs up EVERYTHING.

Rewind backs up your store’s data every single day:

  • Products and Product Images
  • Inventory, Customers
  • Orders, Collections
  • Blogs and Blog Posts
  • Pages
  • Themes and Theme Files
  • Menu Navigation
  • Store Policies
  • Locations
  • Shipping Zones
  • Gift Cards
  • Customer Saved Searches
  • Metadata (for Enterprise plans)
The insightful moment to start using Rewind was realizing that blog posts aren’t backed up with Shopify – Losing years of content / traffic would be disastrous. You could manually do this if you enjoy the process of data backup (who does?), so an automated app is a nice time saver. Rewind is like an insurance policy to save time, money, and reputation if a person or app accidentally screws up your store. Free trial: 7 days Price: $3 – $39/mo (also has Enterprise plan)
Get Rewind here

Infinite Product Options

Shopify limits product options to 3 and total variants to 100. Infinite Product Options by Hulk Apps solves that problem. We’ve used a few apps for product options, this one wins out for ease of use, configuration options, and integration into your store.

Key Features:

  • Unlimited options
  • Chargeable (upsell) options
  • Link product options to products so you can create bundles
Free trial: 14 days Price: Free – $9.99/mo (also have an Enterprise plan for $99.99/mo)
Get Order Automator here
Side note, the same company makes a free metafields editor app: Metafields Custom Field Master. We get a lot of asks for metafield editor apps, this one is good.


Growth is all about experimenting, trying new apps, and executing new marketing tactics. We have experience using all of these apps so if you need help setting up for success let us know how we can help. If you’re looking for tips and tactics, check out the Blog. If you want us to optimize your Shopify site to make it faster and more efficient, head over to our Shopify Optimization Services page. If you need a custom app or feature built, contact us, we love these projects!

Some of our posts contain affiliate links, meaning Speed Boostr could receive a commission if you sign up through these links. We only recommend apps and services we believe in. Please read our affiliate disclaimer for more information.