F-Droid - F-Droid is an interesting alternative for Android users who want to try something different and not have to use the Goole Play store all the time.
Pulse Secure - Pulse Secure provides a consolidated offering for access control, SSL VPN, and mobile device security. Contact Pulse Secure at 408-372-9600 to get a free demo.
APK Pure - Download apk for Android with APKPure APK downloader. NoAds, Faster apk downloads and apk file update speed. Best of all, it's free
StackPath - Secure Content Delivery Network, DDoS, WAF Service
APKMirror - Android Market and APK Downloads
Flexera Software Vulnerability Manager - Flexera Software Vulnerability Manager provides solutions to continuously track, identify and remediate vulnerable applications.