What are some alternatives?
When comparing USPS Informed Delivery and FLEXE Next Day Delivery, you can also consider the following products
Amazon Logistics - Create your own delivery business. Amazon's UPS competitor.
Jiffy - Delivering online shopping 6pm to midnight 🌙(LDN)
ShipMonk - ShipMonk helps you scale your eCommerce business by providing industry-leading order fulfillment services and inventory management software.
Arrive Package Tracker - The best way to track all of your online orders 📦
SendOvernightMail - The fastest way to send time sensitive documents via Fedex
Amazon Same-Day Delivery - Free same-day delivery for Amazon Prime members