Now I simplify the problem.
I try to directly copy and paste the query to confrim it use %3D instead of \'=\'
var xhrSNS = Ti.Network.createHTTPC
URL in browser: Signature=Dt9tXa0Rjl%2Ff6YxZ4JaPfsm%2BT%2BMX03gS712nIKKekAI%3D
URL in Android: Signature=Dt9tXa0Rjl%2Ff6YxZ4JaPfsm%2BT%2BMX03gS712nIWUekAI=