This is an excerpt for my newsletter. Hope you like it. I share multiple ideas like this every week on my newsletter.
The approach used in Idea 1: Finding ideas is difficult when it comes to SaaS products. One approach which is easier than spending hours brainstorming on dead ends is to find popular products that were not executed well. We call it: “Second Mover's Advantage Strategy”.
Messenger channel app - Shopify
Available at - https://apps.shopify.com/messenger
Shopify is a huge market and is often considered saturated. However, you can find products that are in high demand but don’t meet the standards of the users. Messenger channel app allows Shopify users to set products in the menu that allows their shoppers to buy the products through the chat. The user can:
let shoppers browse products and make purchases from your Messenger chat
send automated order updates to customers from Messenger
customize the messages, buttons, and menu item titles that shoppers interact with
add a “Message Us” button to your online store and have real-time conversations with shoppers (requires online store)
provide support to customers with questions about their purchase
fulfill Messenger orders from Shopify
track Facebook sales using your sales channel overview and Analytics pages
“ - 
Why did it get popular?
This app is among the top 5 most installed on the Shopify Store. The biggest reason is that Facebook and Shopify have a great partnership. Most dropshipping users use Facebook as one of the biggest sources to gain shoppers. Moreover, recently (2020) Shopify and Facebook have partnered to offer Facebook Branded Shops. - 
What went wrong?
Despite being one of the most installed apps on the platform it has a rating of 2.4.
Reading through the reviews some of the cons are as follows:
All chat message doesn’t show up
Doesn’t work well on mobile
“Message Us” feature doesn’t work well with Chrome
Internalization feature is not available for all parts of the application
Lacks customization in terms of colors
One standout review was this:
“Love this feature and it works very well. Would give it 5 stars but it needs the following changes:
Why should you do it?
Shopify store is a place where if you create an app like this the level of marketing required will be less as you can leverage from the store itself. Another thing is that there is obviously a demand for this product so if you can improve it then there exists a market for it.
Moreover, this product is from Shopify. Let’s face it a company as big as that wouldn’t care about improving features that quickly given that it is one of the many products that it has created. So if you can move swiftly you have a chance.
What can you change?
Complete Solution: Apart from just improving on the weaknesses, you can also think about targeting other social channels. You can create a complete solution for multiple social media like Instagram, Twitter, etc.
Alternate Market: You can use the idea of selling through messenger to other markets apart from Shopify for example for Food Delivery.