The best replacement for xenapp is xendesktop.

The best alternatives to xenapp are rated as following:
★★★★★  xendesktop
★★★  thinapp
★★★  remoteapp
★★★  xenserver
★★  rds
★★  terminal services
★★  xenapp fundamentals
★  remote desktop services
★  vmware view
★  citrix receiver
★  app-v
★  rds 2012
★  presentation server
★  xenmobile
  metaframe
  xendesktop app edition
  app v
  terminal server
  xenclient

Your alternative for xenapp is not listed? Suggest!
Speaking about xenapp, one probably shouldn't forget about provisioning server.

Other search terms related to xenapp and their ratings are:
★★★★★ provisioning server
★★★★★ pvs
★★★★ app-v
★★★★ access gateway
★★★★ netscaler
★★ xendesktop
hdx
You have in mind a companion for xenapp and it is not yet here? Propose!



Google Trends

Scale is based on the average worldwide traffic of xenapp in all years. Click on graph for more.
xenapp
xendesktop
thinapp