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React-Native, only Android, no firebase: objects are not valid as a React child (found: object with keys {$$typeof, type, key, ref, props, _owner,

I'm building a React Native 0.57 app, which works fine on IOS but fails on Android with the following error:
Objects are not valid as a React child (found: object with keys {$$typeof, type, key, ref, props, _owner, _store}). If you meant to render a collection of children, use an array instead.
throwOnInvalidObjectType ReactNativeRenderer-dev.js:8779:6
reconcileChildFibers ReactNativeRenderer-dev.js:9842:31
reconcileChildren ReactNativeRenderer-dev.js:10319:6
updateHostRoot ReactNativeRenderer-dev.js:10683:6
beginWork ReactNativeRenderer-dev.js:11360:28
performUnitOfWork ReactNativeRenderer-dev.js:14091:21
workLoop ReactNativeRenderer-dev.js:14129:41
renderRoot ReactNativeRenderer-dev.js:14226:15
performWorkOnRoot ReactNativeRenderer-dev.js:15193:17
performWork ReactNativeRenderer-dev.js:15090:24
performSyncWork ReactNativeRenderer-dev.js:15047:14
requestWork ReactNativeRenderer-dev.js:14925:19
scheduleWork ReactNativeRenderer-dev.js:14711:16
scheduleRootUpdate ReactNativeRenderer-dev.js:15429:15
updateContainerAtExpirationTime ReactNativeRenderer-dev.js:15462:28
updateContainer ReactNativeRenderer-dev.js:15494:4
render ReactNativeRenderer-dev.js:16142:20
renderApplication renderApplication.js:59:34
run AppRegistry.js:101:10
runApplication AppRegistry.js:195:26
__callFunction MessageQueue.js:349:47
<unknown> MessageQueue.js:106:26
__guard MessageQueue.js:297:10
callFunctionReturnFlushedQueue MessageQueue.js:105:17
I searched on the Internet et SO (of course), and everybody is talking about firebase which I'm not using.
As far as I remember, with RN 0.56 all was working fine, and since the upgrade to 0.57, this error started to occur.
The workaround is to enable the debugger ... but the release is suffering the same issue.
The issue is happening in the simulator and on the real device.
As the app is working on IOS, I guess this is coming from the android project.
How can I investigate this issue?
UPDATE
I found out that adding import 'core-js' to the top of the index.js file of the app is avoiding the error.
This core-js is a dependency of many package, like react-native itself.
Why is this import solving the issue and why do I have to do it, especially if the iOS version works fine?

cordova.file.* (all directories) are null

I'm working on Ionic mobile app development.
My requirement is to create client side logger to track issues in app. I used the methods mentioned in https://github.com/pbakondy/filelogger, and I could able to create the log file in both Android and iOS.
For the first time when I open the app, it creates the log file in cordova.file.dataDirectory, when I close and reopen the app in i*OS, I'm trying to read the content of the file which was created using the below
$fileLogger.getLogfile().then(function (loggerContent) {
var temp =loggerContent;
});
But the application says
{
"applicationDirectory":null,
"applicationStorageDirectory":null,
"dataDirectory":null,
"cacheDirectory":null,
"externalApplicationStorageDirectory":null,
"externalDataDirectory":null,
"externalCacheDirectory":null,
"externalRootDirectory":null,
"tempDirectory":null,
"syncedDataDirectory":null,
"documentsDirectory":null,
"sharedDirectory":null
}
So I couldn't able to find the file where i saved my logs.
Please help me resolve this issue or if you could recommend me a different method to get around this issue, that would be great!
Thanks for the answers

There is a check list here and should solve your problem :
1-Be sure that the cordova-file-plugin is installed and works in your test environment.
2-Be sure that the cordova.js file is refrenced by your html and before your code usage.
3-Be sure to call your codes after device_ready state :
check this
4-Call your function after a short delay (use setTimeOut in Javascirpt)

Ali's item 4 is very important:
I had a similiar problem on different platforms: cordova.file.dataDirectory was null.
I tracked cordova.file.dataDirectory over the lifecycle and it was first accessed by my Ionic 2 code BEFORE the device ready event was fired.
My "mistake": I wanted to load data during the constructor(!) of a service. Seems too early.

Failed to set remote offer sdp: Failed to create channels

The error happens on these two lines:
mPeerConnectionClient.setRemoteDescription(new SessionDescription(SessionDescription.Type.OFFER, Sdp()));
mPeerConnectionClient.createAnswer();
In which conditions the error can occur?
Update:
This seems to the solution but not yet tested: https://groups.google.com/forum/#!starred/discuss-webrtc/omiojGomEI4

The issue is resolved from comment on this questions:
https://groups.google.com/forum/#!starred/discuss-webrtc/omiojGomEI4

What are the list of Android specific exceptions?

I know some of exceptions are thrown by Android framework. Like ActivityNotFoundException, WindowManager.BadTokenException.
But i am not aware of all other exceptions which are specific to android framework.
Can anybody list possible Android framework specific exceptions with a small description. Or suggest me blogs information which contains the required information.

http://developer.android.com/reference/java/lang/Exception.html
I think here you can find it, "Known Indirect Subclasses", totally 224 exceptions.
Only choose the one started by "Android", here are about 72 exceptions, these should be the list
android.content.ActivityNotFoundException
android.util.AndroidRuntimeException
android.accounts.AuthenticatorException
android.os.BadParcelableException
android.util.Base64DataException
android.hardware.camera2.CameraAccessException
android.database.CursorIndexOutOfBoundsException
android.os.DeadObjectException
android.media.DeniedByServerException
android.support.v4.app.Fragment.InstantiationException
android.opengl.GLException
android.view.InflateException
android.content.IntentFilter.MalformedMimeTypeException
android.content.IntentSender.SendIntentException
android.view.KeyCharacterMap.UnavailableException
android.security.keystore.KeyExpiredException
android.security.keystore.KeyNotYetValidException
android.security.keystore.KeyPermanentlyInvalidatedException
android.util.MalformedJsonException
android.media.MediaCodec.CodecException
android.media.MediaCodec.CryptoException
android.media.MediaDrm.MediaDrmStateException
android.media.MediaDrmResetException
android.accounts.NetworkErrorException
android.os.NetworkOnMainThreadException
android.util.NoSuchPropertyException
android.media.NotProvisionedException
android.support.v4.os.OperationCanceledException
android.content.pm.PackageManager.NameNotFoundException
android.os.ParcelFileDescriptor.FileDescriptorDetachedException
android.os.ParcelFormatException
android.net.ParseException
android.app.PendingIntent.CanceledException
android.support.v8.renderscript.RSDriverException
android.support.v8.renderscript.RSIllegalArgumentException
android.support.v8.renderscript.RSInvalidStateException
android.support.v8.renderscript.RSRuntimeException
android.content.ReceiverCallNotAllowedException
android.os.RemoteException
android.widget.RemoteViews.ActionException
android.media.ResourceBusyException
android.content.res.Resources.NotFoundException
android.database.SQLException
android.database.sqlite.SQLiteAbortException
android.database.sqlite.SQLiteAccessPermException
android.database.sqlite.SQLiteBindOrColumnIndexOutOfRangeException
android.database.sqlite.SQLiteBlobTooBigException
android.database.sqlite.SQLiteCantOpenDatabaseException
android.database.sqlite.SQLiteConstraintException
android.database.sqlite.SQLiteDatabaseCorruptException
android.database.sqlite.SQLiteDatabaseLockedException
android.database.sqlite.SQLiteDatatypeMismatchException
android.database.sqlite.SQLiteDiskIOException
android.database.sqlite.SQLiteDoneException
android.database.sqlite.SQLiteException
android.database.sqlite.SQLiteFullException
android.database.sqlite.SQLiteMisuseException
android.database.sqlite.SQLiteOutOfMemoryException
android.database.sqlite.SQLiteReadOnlyDatabaseException
android.database.sqlite.SQLiteTableLockedException
android.provider.Settings.SettingNotFoundException
android.database.StaleDataException
android.view.Surface.OutOfResourcesException
android.view.SurfaceHolder.BadSurfaceTypeException
android.nfc.TagLostException
android.util.TimeFormatException
android.os.TransactionTooLargeException
android.media.UnsupportedSchemeException
android.security.keystore.UserNotAuthenticatedException
android.view.WindowManager.BadTokenException
android.view.WindowManager.LayoutParams#token
android.view.WindowManager.InvalidDisplayException

The following are the exceptions that are supported by Android:
1.) InflateException : This exception is thrown When an error conditions are occurred.
2.) Surface.OutOfResourceException: This exception is thrown When a surface is not created or resized.
3.) SurfaceHolder.BadSurfaceTypeException: This exception is thrown from the lockCanvas() method, when invoked on a Surface whose is SURFACE_TYPE_PUSH_BUFFERS
4.) WindowManager.BadTokenException: This exception is thrown at the time of trying to add view an invalid WindowManager.LayoutParamstoken.

java.lang.NoSuchMethodError: android.app.ANRAppManager.dumpMessageHistory

My Android App reported some crash report:
java.lang.NoSuchMethodError: android.app.ANRAppManager.dumpMessageHistory
at android.app.ActivityThread$ApplicationThread.dumpMessageHistory(ActivityThread.java:1177)
at android.app.ApplicationThreadNative.onTransact(ApplicationThreadNative.java:609)
at android.os.Binder.execTransact(Binder.java:351)
at dalvik.system.NativeStart.run(Native Method)
A lot of android device reported the same crash:
Android|Android=>3
android|Coolpad=>1
Android|Lenovo=>1
Android|VIVO=>2
apsl|Lenovo=>1
apsl|Samsung=>2
ARES|AE912=>3
Coolpad|Coolpad=>2
COWW|C920=>5
GoDonie|GoDonie F7=>1
HESM|HSEM TD777=>2
HMI|H2=>1
huawei|huawei=>2
intki|intki_E86=>3
ioco|i9100 X6=>1
Lenovo|Lenovo A820T=>1
MEEG|MEEG_101M=>2
NEWLAND|N003=>2
SAST|SAST YC500=>1
But I didn't find "dumpMessageHistory" in my code, please help, thanks!!

The class android.app.ANRAppManager can not be found in Android Application Framework (/frameworks/base/core/java/android/app). Probably it is a vendor supplied class for MTK chips. Whenever there is an ANR raised, ANRAppManager.dumpMessageHistory would be invoked.
The best advice would be to keep track of all cases of ANR that takes place in your app and try to fix it.