Develop Reference

Android: subscriptionManager.getActiveSubscriptionInfoList() gives null, although SIM is present

Using SubscriptionManager for fetching sim details, but for few users subscriptionManager.getActiveSubscriptionInfoList() is returning null(READ_PHONE_STATE permission is granted), even if sim is present in the device.
val subscriptionManager: SubscriptionManager = (SubscriptionManager) context.getSystemService(Context.TELEPHONY_SUBSCRIPTION_SERVICE);
val subscriptionInfos = subscriptionManager.getActiveSubscriptionInfoList();
Is there any other way to fetch sim details?

How to check if SIM is active?

I have a use case where I need to check whether a SIM is active in the device. In older devices, I can use TelephonyManager to get the SIM state and check whether it is SIM_STATE_READY. The issue is with API 22 and above.
Using SubscriptionManager, when I call getActiveSubscriptionInfoList, it sends me details about the SIMs present, even if I have turned them off. I went through the documentation of SubscriptionManager but couldn't find a similar method to check SIM's state. Using TelephonyManager in API above 22 gives information only about the default SIM, I would like to know this about both slots in dual SIM phones. Also, I found an overloaded variant of getSimState in TelephonyManager which does accept the slot as a parameter, but that got introduced in API 26. I would like a solution that will work in APIs 22-25 as well.
Is there a way I could identify that even though the SIM is present in the device, it isn't active?

You can check by like this if Device is dual sim
SubscriptionManager sManager = (SubscriptionManager) context.getSystemService(Context.TELEPHONY_SUBSCRIPTION_SERVICE);
SubscriptionInfo infoSim1 = sManager.getActiveSubscriptionInfoForSimSlotIndex(0);
SubscriptionInfo infoSim2 = sManager.getActiveSubscriptionInfoForSimSlotIndex(1);
int count = 0;
if (infoSim1 != null ) {
count++;
}
if (infoSim2 != null){
count++;
}
count decides that how many sims are active.
OR
You can get the count then check one by one
sManager.getActiveSubscriptionInfoCount()
Hope it's work.

TelephonyManager manager = (TelephonyManager)context.getSystemService(Context.TELEPHONY_SERVICE);
if (manager.getPhoneCount() == 2) {
// Dual sim
}
Examples here

How to get IMEI of all SIM cards by using Lollipop MR1 Multiple SIM support (via SubscriptionManager)?

As announced for Lollipop MR1, SubscriptionManager and its SubscriptionInfo provide lots of information about all (active) SIMs, but I'm missing their IMEIs.
I get info about SIMs like this:
SubscriptionManager sm = SubscriptionManager.from(context);
List<SubscriptionInfo> sil = sm.getActiveSubscriptionInfoList();
if (sil != null) {
for (SubscriptionInfo subInfo : sil) {
Log.d(TAG, "SubInfo:" + subInfo);
}
} else {
Log.d(TAG, "SubInfo: list is null");
}
Am I missing something or can we still only get the IMEI (only of the 1st SIM card) via telephonyManager.getDeviceId()?

The method
public String getDeviceId(int slotId)
is available under TelephonyManager in API 23. slotId is just a number from 0 to the number of SIMs - 1.
In API 22, the same method exists but is hidden. You need to use reflection to call it.

The IMEI is used to identify the device, not the SIMs.So yes, you can only get the IMEI through telephonyManager.getDeviceId().
UPDATE: So it turns out I was wrong and a device can have an IMEI for each SIM card. I've found this answer in StackOverflow that can help you.
Android : Check whether the phone is dual SIM

How can I get the ICCID number of the phone?

How can I get the ICCID number of the phone?
I looked in the TelephonyManager class, but didn't found there a way to get the ICCID number, there is only a method which tells if the ICC card is present.

I believe getSimSerialNumber() will get iccid.
UPDATE for Android 5.1 (credit Erick M Sprengel)
"Multiple SIM Card Support" was added for Android 5.1 (API 22).
Instead of using getSimSerialNumber, you can use SubscriptionManager.
SubscriptionManager sm = SubscriptionManager.from(mContext);
// it returns a list with a SubscriptionInfo instance for each simcard
// there is other methods to retrieve SubscriptionInfos (see [2])
List<SubscriptionInfo> sis = sm.getActiveSubscriptionInfoList();
// getting first SubscriptionInfo
SubscriptionInfo si = sis.get(0);
// getting iccId
String iccId = si.getIccId();
You will need the permission: (credit Damian)
<uses-permission android:name="android.permission.READ_PHONE_STATE" />

It's best not to use this, as this is one of the identifiers that recently got restricted, just as was done recently on Android 10.
On Android 11 (API 30), even if you don't target it, you will most likely get just an empty string.
The recommendation of what to use is getSubscriptionId instead (requires READ_PHONE_STATE permission).
The reason:
Returns the ICC ID. Starting with API level 30, returns the ICC ID if
the calling app has been granted the READ_PRIVILEGED_PHONE_STATE
permission, has carrier privileges (see
TelephonyManager#hasCarrierPrivileges), or is a device owner or
profile owner that has been granted the READ_PHONE_STATE permission.
The profile owner is an app that owns a managed profile on the device;
for more details see Work profiles. Profile owner access is deprecated
and will be removed in a future release.
so it returns "the ICC ID, or an empty string if one of these requirements is not met" . For third party apps, this means you will probably always get an empty string.
If you don't meet these (and you usually don't), you can use it.
final SubscriptionManager subscriptionManager = SubscriptionManager.from(context);
final List<SubscriptionInfo> activeSubscriptionInfoList = subscriptionManager.getActiveSubscriptionInfoList();
And then for each of them, you can use subscriptionInfo.getIccId() .

#Jakar, thank you very much! Here's the same code in C# using Xamarin / Mono.Android
Requires the permission set in your AndroidManifest.xml
<uses-permission android:name="android.permission.READ_PHONE_STATE" />
Simple C#
using System.Collections.Generic;
using Android.Telephony;
// ...
protected override void OnCreate(Bundle bundle)
{
base.OnCreate(bundle);
// Requires, android.permission.READ_PHONE_STATE
SubscriptionManager sm = Android.Telephony.SubscriptionManager.From(Android.App.Application.Context);
IList<SubscriptionInfo> sis = sm.ActiveSubscriptionInfoList;
SubscriptionInfo si = sis[0];
string carrier = si.CarrierName;
string iccId = si.IccId;
string phoneNum = si.Number;
System.Diagnostics.Debug.WriteLine("Carrier: " + carrier);
System.Diagnostics.Debug.WriteLine("SIM Card IccId: " + iccId);
System.Diagnostics.Debug.WriteLine("Phone Number: " + phoneNum);
// Bonus, Get the IMEI Id (aka, DeviceId)
TelephonyManager tm = (TelephonyManager)GetSystemService(Android.Content.Context.TelephonyService);
string deviceId = tm.DeviceId;
System.Diagnostics.Debug.WriteLine("Device Id: " + deviceId);
}
Both SubscriptionManager and SubscriptionInfo are found under the Android.Telephony namespace
Truth be told this example was needed to activate my phone on the fly and not having the SIM card tool handy to pull it out. And, my eyes aren't what they use to be. View it on DroidTelephonySimInfo.cs on gist.github.com

Detect the status of two SIM cards in a dual-SIM Android phone

I want to detect whether two SIM cards are there in my dual-SIM android phone programmatically. I found one API (TelephonyManager.getSIMState()), but it is for normal single-SIM phones. Are there any APIs to detect whether or not two SIMs are inserted in my dual-SIM phone?

Android does not support multiple SIMs, at least from the SDK. Device manufacturers who have created multi-SIM devices are doing so on their own. You are welcome to contact your device manufacturer and see if they have an SDK add-on or something that allows you to access the second SIM.
Edit: (15th July, 2015)
Since API 22, you can check for multiple SIMs using SubscriptionManager's method getActiveSubscriptionInfoList(). More details on Android Docs.

From now, if the phone is MTK powered one, you can use TelephonyManagerEx class from MediaTek SDK.
Take a look at the docs.

final SubscriptionManager subscriptionManager = SubscriptionManager.from(getApplicationContext());
final List<SubscriptionInfo> activeSubscriptionInfoList = subscriptionManager.getActiveSubscriptionInfoList();
int simCount = activeSubscriptionInfoList.size();
btnBack.setText(simCount+" Sim available");
Log.d("MainActivity: ","simCount:" +simCount);
for (SubscriptionInfo subscriptionInfo : activeSubscriptionInfoList) {
Log.d("MainActivity: ","iccId :"+ subscriptionInfo.getIccId()+" , name : "+ subscriptionInfo.getDisplayName());
}

Well, this is not fool proof. But if you have two SIMs which are on two different network operators you can try something like this:
PhoneServiceStateListener listener = new PhoneServiceStateListener(this);
tm.listen(listener, PhoneStateListener.LISTEN_SERVICE_STATE);
.
.
.
class PhoneServiceStateListener extends PhoneStateListener {
Context context = null;
public PhoneServiceStateListener(Context context) {
this.context = context;
}
public PhoneServiceStateListener() {
}
#Override
public void onServiceStateChanged(ServiceState serviceState) {
if (serviceState.getState() == ServiceState.STATE_IN_SERVICE) {
//You get this event when your SIM is in service.
//If you get this event twice, chances are more that your phone is Dual SIM.
//Alternatively, you can toggle Flight Mode programmatically twice so
//that you'll get service state changed event.
}
super.onServiceStateChanged(serviceState);
}
}
Ideally you'll get SIM service state changed event for both the SIMs and then you can check for network operator name or something like that to check if you have two SIM cards. But you need to have two SIM cards running on two different networks.