Software discounts / applications

I use Shopify as a platform for my store, but since I'm just starting and I have little money, I look for good deals, cheap applications and discounts. Mainly from the Shopify application store.
Can anyone share good comments about this? Like the discounts you found that are redeemable.

For email marketing use Omnisend, and I discovered that they have a discount code, for example. Since I really like your free trial version, it was easy to subscribe to the premium plan.
Here is the discount if someone is interested: OMNI10
Conditions: 10% discount for 3 months for the monthly premium plan. Redeem before March 31.
As I understand it, anyone can use it so yes.