Mobile app issues with LTM on version 13.1.0.3

What TCP profile (mobile?) are you using? The network stack of v13 has had a major overhaul and the default settings have changed. The 0-size windows could suggest a buffer size issue (did you enable auto buffer tuning?), and you need to do some TCP performance tuning.

Please see:

TCP Configuration Just Got Easier: Autobuffer Tuning

K03553427: Using optimized TCP profiles

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