Apps that can be sold on shopify store

I am looking for a developer to create productivity apps that can be sold on my Shopify store. The ideal candidate should have experience in developing productivity apps and should be able to meet my specific requirements. The budget for each app is less than $500.

Skills and experience required:
- Experience in developing productivity apps
- Familiarity with Shopify store integration
- Ability to meet specific requirements and deliver high-quality apps within budget