This is an updated list of malware analysis sandboxes and services I use during my everyday work. They are very useful in case you don't have resources to build up your own sandbox or you just don't feel like doing it. I hope you enjoy and I invite you to suggest other links.
Joe Sandbox Document Analyzer (MS Office files, PDF and RTF)
VisualThreat (Android and Apple iOS files)
XecScan (PDF and MS Office files)