Yes, both OneSignal and PushAd offer a Free Trial.
OneSignal is designed for Individuals, Freelancers, Large Enterprises, Medium Business and Small Business.
PushAd is designed for Individuals, Large Enterprises, Medium Business and Small Business.
Pricing for OneSignal Starts at $9/Month whereas for PushAd Starts at $5/Month.
Some top alternatives to OneSignal includes VWO Engage, PushEngage, Push Monkey, PushBots, PushAlert, Push.World, TITANPush, WonderPush, Notificare, PushNinja and Webpushify.
Some top alternatives to PushAd includes VWO Engage, OneSignal, PushAssist, PushBots, PushAlert, Push.World, Adrack Web Push, PushPushGo, PushNinja, Adrenalead and SmartPush.