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Overall rating
Counts per rating level
  • 95% of ratings are 5 stars
  • 3% of ratings are 4 stars
  • 1% of ratings are 3 stars
  • 0% of ratings are 2 stars
  • 2% of ratings are 1 stars
What merchants think

Feedback submitted

Merchants appreciate this app for its ability to boost sales and increase average order value through features like bundle offers and free gifts. It's praised for its seamless integration with Shopify themes and its user-friendly customization options. The customer service is often highlighted as responsive and excellent, with specific team members commended for their support. The app's smooth performance and speed are also noted, making it feel like a natural part of the store's theme.

November 30, 2023

This is the worst app! It was recommended by a team that's helping me with the website, the cart was changed to this one before Black Friday, the app works for certain people but for others don't. We got complaints from clients that couldn't add items to cart and when we test some of us could, some of us couldn't and this happened in the busiest time of the year. DO NOT USE!

United States
9 days using the app
Monster Apps replied December 2, 2023

Sorry to hear this!!!! 😅 We were in 1000% help mode throughout this period to help with any theme, App incompatibility or cart issues anyone might have. Looking back i couldn't see any messages from your team.

Unfortunately it's hard to pinpoint exactly what may have happened without getting to do a deeper dive. Sometimes there can be issues with conflicting themes, carts and other apps that we can't solve without investigating further.

If you decide to download the app again please feel free to reach out and let us know what you are facing here.

October 25, 2023

This app totally messed up my currency. 60 USD product was in cart for 2000 USD!!! also it is slowing my website a lot!!! If there would be an option to give 0 stars that is what I would choose!!!

2 days using the app
Monster Apps replied October 29, 2023

Sorry to hear this. It's extremely rare for this currency issue to have happen as we use shopify best practices. It would most likely have been due to a conflict with another app or theme issue.
I couldn't see any conversations between yourself and the support team.
Happy to help get this sorted asap if you decide to download the app again. :)

Regards Ty.

June 9, 2023

Strongly not recommended to use!!

This is the worst Shopify plugin I have ever used. It blocks the add-to-cart event and forces the store's data to be reported to the server. At this moment, their server is down, causing multiple stores of mine to have no add-to-cart events during peak traffic periods!! Unable to contact any customer service from them, resulting in a loss of tens of thousands of dollars for nothing.

Monster upsells cart is disabled: Network Error;
Monster upsells cart is disabled: Network Error;
Monster upsells cart is disabled: Network Error;
Monster upsells cart is disabled: Network Error;

United States
16 days using the app
Monster Apps replied June 9, 2023

Co-Founder here. Team was on quick… and checked further. Was a short Shopify downtime. Our record show it wasn’t long at all though and stores will use standard Shopify checkout if cart is skipped.
Just DM’d u directly. Happy to do everything we can to get things running smooth for you.

April 7, 2023

Worst support we've received from any app provider over the past five years we've been on Shopify. The app was breaking our 'Add to Cart' button so that when it was clicked, nothing would happen. It would take quite a few clicks at times to add an item to the cart, and even then our old cart would load, not the MonsterUpsell version.

I sent a screen sharing video to support regarding the issue, and they said they'd get back to me in 24-48 hours. 48 hours past, so I followed up to see what the status was.

Here's the response I received, "Our dev team and even the head dev already checked the issue and tried their best to make our app work in your store. But unfortunately, we can't support your theme and therefore we can't do anything from our end."

Disappointing for sure, but I was understanding, until I went to uninstall the app, and saw that the dev team chose to leave the app enabled on our LIVE theme when they knew it was breaking our 'Add to Cart' button.

First of all, they should have been testing the app on a backup theme that was not published/live, and second of all, they should have immediately disabled the app once they confirmed they couldn't fix the issue. That's just basic, developer 101 type of stuff.

It just shows how little they care about their customers. I'll be finding another in-cart upsell app, and I recommend you do the same.

United States
3 days using the app
Monster Apps replied April 7, 2023

Ty here one of the founders... 🥲🥲 Store owners are the heart of our business and the team works hard to support as best they can... (see past reviews)
Trust me - it kills us to hear this kind of feedback. 😅

Yes totallllllyyy agree... Testing on backup themes is our normal standard operating procedure. I'll be chasing down how and why this situation played out.

As for compatibility...
Unfortunately yes... your theme clashes with the loading of our app. This is a rare situation. We had our main devs on it for 2 days straight and couldn't solve it.
Sorry - wish I had a better answer here. 🥲🥲

June 29, 2023

there's no free plan, it makes you pay 13$ a month before you can even open the app and look what it offers

Key Saviours
1 minute using the app
Monster Apps replied June 29, 2023

Correct - Only Shopify partners and partner stores can use the app for free.

When you enter the app you will have to accept charges of the base plan. However you will only be charged if you exceed the 10 day free trial.

August 15, 2022

So stupid, the worst app. thief app. "This campaign will show up on the products you choose below. you can show it on all products or specific"
The campaign will be triggered by sitewide products, not a specified collection or product. The discount will be applied to all products, not specified collections or products.

4 months using the app
Monster Apps replied August 16, 2022

As per chat desk discussion: You were using the app incorrectly. 😅 We have 1800+ stores making great upsell $$$ without a problem. The campaign chosen was a sitewide offer with trigger products.... (not built the way you wished to use it with collections) - I'm sorry if the purpose of the campaign was misunderstood.
Thanks for the feedback - we will always take it on and want to make things clearer for merchants.

To clarify: This is not a bug. It's the way the specific campaign was built.

Edited May 12, 2022

This app takes 52% of speed from your website. Before installing this app our Mobile Site Speed Score was 91 and now with the Cart Upsell Monster app our Mobile Site Speed Score is 47. Do not recomend this app!!!

Scandinavian Goods
About 1 month using the app
Monster Apps replied May 12, 2022

UPDATE: We are currently beta testing the lightning speed update RIGHT NOW! Reach out if you want to be in the beta tests. 💃⚡️
Hi team, We're very sorry to hear this.
Monster is light on code - however, sometimes themes react a bit slower the way it's set up. Good news is we are releasing our ⚡️⚡️ lightning update VERY SOON!
If you have any issues with speed - no worries 🙏🏻 (Reach out to the team, We will make things right) 🥰

This update will code the cart more direct into theme which will make it the fastest thing on the planet 💃⚡️.

August 22, 2022

Unfortunately this app broke my website for all Safari users, which is the majority of my clients. I've been paying a lot of money in marketing while my clients are not able to do checkouts

Holee Jewelry
United States
11 days using the app
Monster Apps replied August 22, 2022

We have 1000's of stores using Monster seamlessly on all browsers and 100's of themes. I see you never reached out to the support team for help 😢. Sorry to hear this is your experience with your store. We are always here to work with integrations. If you reinstall... please reach out to team the team.