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