Top 5 International Calling Apps Compared: Which One Is Worth It?

Ever tried to call home from abroad and ended up staring at a “Call Failed” message, wondering if your phone just hates you? You’re not alone. Dozens of apps exist in 2025 that promise to make international calling simple, but most leave you juggling Wi-Fi, unstated costs, or erratic audio.

Which app, then, genuinely functions without making your patience or wallet turn upside down?  To determine which of the top 5 global calling applications is worth your time (and money), let’s break them down.

What to Look for in an Global Calling App

Before we compare these apps, here’s your checklist to make a better decision:

• Call Quality: Nobody likes robotic voices or dropped calls mid-sentence.
• Coverage: Can you reach landlines and mobiles worldwide, or only other app users?
• Cost Transparency: Are rates clear, or are you secretly funding someone’s vacation?
• Security: Encryption matters. Your conversations shouldn’t be public content.
• Ease of Use: If it’s complicated, you’ll give up mid-installation.

Keep these points in mind, because what looks good on paper might feel like a nightmare in your hand.

Top 5 International Calling Apps at a Glance (Pros & Cons)

Here’s a quick snapshot of how the big players stack up:

WhatsApp

• Pros: Free app-to-app calls, widely used.
• Cons: Only works if the other person is online and has the app.
• Best For: Staying in touch with friends and family who also use WhatsApp.

Facebook Messenger

• Pros: Free app-to-app calls, video calls, widely recognized.
• Cons: Can be heavy on data, only works if the other person is online and uses Messenger.
• Best For: Chatting with friends and family already on Facebook.

Slick

• Pros: Free app-to-app calls anywhere, cheap plans for landlines & mobiles, end-to-end encryption, global coverage, and making calls to offline numbers and non-app users.
• Cons: Newer app as compared to others.
• Best For: Anyone who wants stress-free global calling without having to worry about app-to-app calling and sky-high rates, including expats and travelers.

Viber

• Pros: Free app-to-app calls, stickers.
• Cons: Limited reach to non-Viber users.
• Best For: Social chat and casual calls.

Google Voice

• Pros: Works on multiple devices, reliable for US numbers.
• Cons: Limited global reach, costs vary.
• Best For: Calling US numbers from abroad.

Why Slick Stands Out

Let’s be honest: most apps are good for chatting with friends on the same platform, but what about calling a number that isn’t on the app or doesn’t use the internet? Slick fixes that with these features:

• Free app-to-app calls worldwide
• Call offline numbers
• Cheap calling plans for over 200 countries
• Make calls to non-app users
• Make calls to landlines worldwide
• Zero hidden charges
• No roaming shocks
• End-to-end encryption for secure calls
• Send mobile recharge and buy data eSIMs from the same app

Final Verdict: Which App Is Worth It?

If you mostly call friends who are online and already use an app, WhatsApp or Messenger works fine. However, Slick is the only international calling app that makes calling landlines, mobiles, non-app users, and even offline numbers easy. So, are you prepared to put an end to worrying about failed international calls? Download the Slick app and start making hassle-free calls to landlines and mobiles worldwide.