Best SIP apps and softphones for Android, iPhone, Windows, Mac and Linux
In short
On a computer, almost any free SIP app works: MicroSIP on Windows, Linphone everywhere else. On a phone, the hard part is ringing when the screen is locked. Free apps manage it on Android after a couple of settings. On an iPhone, you need a paid app with push, such as Groundwire.
A softphone is a phone that lives in an app, on your mobile or your computer. A SIP app is a softphone that signs in with SIP, the standard most internet phone services use. Give it a SIP account and it makes and takes calls like a normal phone.
The app
Linphone, MicroSIP, Groundwire... the buttons and the sound
A SIP account
Username, password and server from a provider
Real phone numbers
Mobiles and landlines in any country
Here's the part most lists skip: the app does not give you a phone line. It is the handset. The line comes from your SIP provider, and that decides your rates, your number and who you can call. Any app on this page works with any normal SIP account, including ours, paid in crypto.
One more thing: in India, "SIP" also means a monthly investment plan. This guide is about calling apps only.
App finder
Find the right SIP app in 30 seconds
Pick your device and what matters to you. The answer comes from the facts in the comparison below, in our order of preference.
1. Where will you make calls?
2. Budget
3. Must it ring when the phone is locked?
4. Your SIP password
Our picks for you
Best fitGroundwire
An iPhone that rings when it is locked
$9.99 on iPhone, $9.49 on Android, one-time
When locked: Rings, via the app maker's server
Watch out: Push works by storing your SIP login on Acrobits' server, which signs in for you.
12 apps that work with any provider's SIP login. Prices are from US app stores and official sites, checked on 26 October 2026; they differ a little by country.
Locked phone: whether the app rings a locked Android or iPhone with a login from another provider (not the app maker's own service). Encryption needs your provider to support it too.
The big one
Why SIP apps miss calls on a locked phone
To hear a call coming, a SIP app has to stay signed in to your provider. Phones hate that. To save battery, iPhone and Android put apps to sleep soon after you lock the screen, and a sleeping app hears nothing.
There are only three ways around it. Each one decides whether the phone rings, how much battery it costs, and who ends up holding your SIP password. No other guide we found explains this, and it matters more than any feature list.
1. The app stays awake
Linphone on Android, every computer app
Caller
Your provider
App, kept running
Your login never leaves your device.
iPhone does not allow it. Android needs the battery saver turned off for the app.
2. The app maker's server waits for you
Groundwire, Acrobits Softphone, Bria
Caller
Your provider
App maker's server
Push wakes phone
Works on iPhone with almost any provider, and saves battery.
That server holds your SIP password and signs in as you.
3. Your provider sends the push
Linphone with Linphone's own accounts
Caller
Provider with push
Push wakes phone
Rings reliably and nobody else holds your login.
Only works when the provider and the app are built for each other.
Privacy check before you pick a push app
Groundwire and Acrobits Softphone send your SIP login to Acrobits' server, which signs in for you while the app sleeps. Acrobits deletes it if you turn push off or the phone is unheard from for more than 7 days. Bria's push service signs in on your behalf too. That is how push works with any provider, and the companies are open about it. If you would rather nobody else held your password, use Android with an app kept running, or a computer.
iPhone
Best SIP apps for iPhone
An iPhone has no built-in SIP calling, and iOS stops background apps quickly. Apps that ring when locked use Apple's VoIP push, which shows the normal full-screen iPhone call screen.
Android used to have SIP calling built into the phone app. Google removed it in Android 12, so every phone now needs an app. The good news: Android lets a free app stay awake, so you do not have to pay for push.
Every app on this page asks for the same details. The labels change; the values do not.
1
Username
Also called: User, SIP user, extension, account
The account name, without any @ part.
2
Password
Also called: Secret, auth password
Case-sensitive. Paste it rather than typing it.
3
Server
Also called: Domain, host, registrar, proxy
The server name only, such as sip.example.com, with no sip: in front.
4
Transport
Also called: Protocol: UDP, TCP or TLS
Pick exactly what your provider says. A mismatch is the top reason a first login fails.
Step-by-step screens for Linphone are in the Linphone setup guide, and short steps for Zoiper, MicroSIP and phone systems are on the SIP account page. Dial numbers with the + and country code.
Troubleshooting
Fixing common softphone problems
The same six problems turn up in every app. Find yours, then try the fix.
It does not ring
On a phone, the app was put to sleep. Use an app with push, or keep it running and exempt it from battery saving. On a computer, the app was closed or the computer slept.
Registration failed, 401 or 403
The server turned the login down. Paste the username and password again, check there is no @ part in the username, and use the exact server name.
408 timeout, or it never connects
The app cannot reach the server. Check the server name, try another transport (UDP, TCP or TLS), or another network. Some hotel and office Wi-Fi blocks SIP.
You hear them, they cannot hear you
One-way audio is nearly always the router. Turn off SIP ALG, leave STUN or ICE on in the app, or switch to TCP or TLS.
The battery drains fast
The app is holding a connection open all day. An app with push uses far less power, or raise the registration interval to around 10 minutes.
Calls drop on mobile data
The network forgot the connection between check-ins. Lower the registration interval to 2 to 10 minutes, or move to TCP.
How we chose
How we picked these apps
Every app here signs in with a normal SIP login from any provider. Apps tied to one company's own phone system were left out. Nearly all were updated in 2026. Telephone has had no new release since 2022, and we say so.
Every fact comes from the app's official website, documentation or store listing, read on 26 October 2026. We did not run lab tests and we do not invent scores. Where a maker does not say something, such as how an app rings when locked, we write "not documented" rather than guess.
We do not make any of these apps and none of them pay us. We sell SIP accounts that work in all of them, which is why we care which app you end up with.
A SIP account for any of these apps, paid in crypto
One login works in every app on this page: calls to 202 countries from $0.001/min, billed by the second on most routes, 10 calls at once. The login is free with $5.00 or more of credit, and there is no ID, no email and no card.
Works in Linphone, MicroSIP, Zoiper and any other SIP app
A number for incoming calls and caller ID, if you add one
Prepaid credit, so a stolen login cannot cost more than your balance
Push apps such as Groundwire sign in to us from their own servers. That is a standard SIP sign-in, but we have not yet tested every push app ourselves.
Softphone questions, answered
Is there a free SIP app that rings on a locked iPhone?+
Not with a login from another provider. An iPhone only wakes an app for a call through a push, and the apps that send one for any provider charge for it: Acrobits Softphone ($6.99 once), Groundwire ($9.99 once), Bria Mobile (subscription) or Zoiper's push ($0.99 a month). Free apps like Linphone ring only while they are open.
Do I need a SIP account to use a softphone?+
Yes. The app is only the phone. A SIP account from a provider gives it a username, password and server, and that provider connects your calls to real phone numbers. Without one, most apps can only call other app users.
What is the best free softphone?+
Linphone if you want one free app on every device, MicroSIP if you only need Windows. Both are open source, both encrypt calls when your provider supports it, and both were updated in October 2026.
Are softphones secure?+
They can be. Look for TLS, which hides your login and who you call, and SRTP or ZRTP, which encrypt the sound. Both ends need to support them, so check your provider too. Apps that ring through their maker's server also hand that server your SIP password.
How much data does a SIP call use?+
About 80 MB an hour in total on G.711, the codec phone networks use, counting both directions and network overhead. Opus, used by most modern apps, needs roughly half that. A 10-minute call is a few megabytes either way.
Can one app use several SIP accounts?+
Most can. Linphone, Groundwire, Bria and Sipnetic hold several at once. MicroSIP stores several but keeps one online at a time, and Zoiper charges for extra accounts on Android.
Does Android still have built-in SIP calling?+
No. Google removed it in Android 12, so the SIP option in the phone app is gone on new phones. Install a SIP app such as Linphone instead.
Can I use the same SIP login on my phone and my computer?+
Usually, yes. Sign in to the same account on both and an incoming call rings on whichever is online, often on both. Some providers allow only one device per login, so check with yours.
