OneSignal - Customer engagement platform used by over 1 million developers and marketers; the fastest and most reliable way to send mobile and web push notifications, in-app messages, emails, and SMS.

Rave Alert - Rave Alert is a multi-modal emergency notification system used by state and local governments, colleges, hospitals and universities.

Gravitec.net - Gravitec.net is a smart web push service that lets you boost subscribers through customizable prompts and automatically target your content to the right audience.

DialMyCalls - The easy to use mass and emergency notification platform. Send a phone call, text message or e-mail to your entire list of people in seconds.

Truepush - Unleash limitless possibilities with Truepush and save up to $600 monthly. Free up to 10K Subscribers on all features.

Call-Em-All - Call or send messages to friends and family members as well as other people who are online. The app allows you to create a message and send it out to multiple devices and pages.