I offer five apps in the Shopify app store that I personally developed and maintain since 2017:
Rapid Reviews is the fastest product reviews and questions app for Shopify stores. It is a full featured app that adds deep search to your product reviews and questions.
Image Sitemap submits all of your Shopify images to Google and monitors your image indexing performance over time.
PageSpeed Monitor charts your Shopify theme's Google PageSpeed Insights data over time.
API Helper is a code-based Shopify API connector for ajax subscriptions to Klaviyo, Mailchimp, Omnisend, Shopify Discounts, and Shopify Customer.