Losant - Losant makes building connected experiences and solutions easy.
ThingSpeak - Open source data platform for the Internet of Things. ThingSpeak Features
C3 IoT - C3 IoT enables energy companies to realize the full benefit of their IoT and system investments.
Azure IoT Hub - Manage billions of IoT devices with Azure IoT Hub, a cloud platform that lets you easily connect, monitor, provision, and configure IoT devices.
Hologram.io - Cellular IoT connectivity that powers innovation
AWS IoT Analytics - IoT Management