[General Questions and Answers] mdm5mdm0:
My phone is a Nexus 5 with android 6.0.1 (M4B30X) all stock untouched (rooted).

I removed the apps I don't need (battery increased to 3 days), this has caused some apps to crash, a total of (4) apps crashed out of (53) total, I could do without some, but it seems I cannot find a mail app, I liked K-9 but unfortunately it crashes without saying why?

As I am a windows user, I am struggling to investigate android stuff, .. if any experts here could give me some ideas, I would be most grateful, ..

I also tried: Email_3.0.0.39_160613.apk, BlueMail_1.9.2.11.apk, FastMail_1.05.06.apk, K-at_Mail_Pro_1.14.apk, K-9_Mail_5.010.apk, K-9_Mail_5.114.apk. Some of them launch, download emails but crash once trying to open an email item.

K-9 which I like, it crashes at launch.

I am suspecting dependencies on the apps removed below:

Here is my list of Removed/Kept Apps:

--KEPT--/system/priv-app/TeleService

--KEPT--/system/priv-app/TelephonyProvider

--KEPT--/system/priv-app/Telecom

--KEPT--/system/priv-app/SystemUI

--KEPT--/system/priv-app/StatementService

--KEPT--/system/priv-app/Shell

--KEPT--/system/priv-app/SettingsProvider

--KEPT--/system/priv-app/Settings

--KEPT--/system/priv-app/GooglePackageInstaller

--KEPT--/system/priv-app/GoogleDialer

--KEPT--/system/priv-app/GoogleContacts

--KEPT--/system/priv-app/ExternalStorageProvider

--KEPT--/system/priv-app/DefaultContainerService

--KEPT--/system/priv-app/ContactsProvider

--KEPT--/system/priv-app/CalendarProvider

--KEPT--/system/app/Stk

--KEPT--/system/app/PacProcessor

--KEPT--/system/app/CertInstaller

--KEPT--/system/app/BluetoothMidiService

--KEPT--/system/app/Bluetooth

--REMOVED--/system/priv-app/WallpaperCropper

--REMOVED--/system/priv-app/VpnDialogs

--REMOVED--/system/priv-app/Velvet

--REMOVED--/system/priv-app/TagGoogle

--REMOVED--/system/priv-app/SprintHiddenMenu

--REMOVED--/system/priv-app/SharedStorageBackup

--REMOVED--/system/priv-app/SetupWizard

--REMOVED--/system/priv-app/ProxyHandler

--REMOVED--/system/priv-app/PrebuiltGmsCore

--REMOVED--/system/priv-app/Phonesky

--REMOVED--/system/priv-app/OmaDmclient

--REMOVED--/system/priv-app/MusicFX

--REMOVED--/system/priv-app/MmsService

--REMOVED--/system/priv-app/MediaProvider

--REMOVED--/system/priv-app/ManagedProvisioning

--REMOVED--/system/priv-app/Launcher2

--REMOVED--/system/priv-app/InputDevices

--REMOVED--/system/priv-app/GoogleServicesFramework

--REMOVED--/system/priv-app/GooglePartnerSetup

--REMOVED--/system/priv-app/GoogleOneTimeInitializer

--REMOVED--/system/priv-app/GoogleLoginService

--REMOVED--/system/priv-app/GoogleFeedback

--REMOVED--/system/priv-app/GoogleBackupTransport

--REMOVED--/system/priv-app/GCS

--REMOVED--/system/priv-app/FusedLocation

--REMOVED--/system/priv-app/DownloadProvider

--REMOVED--/system/priv-app/ConfigUpdater

--REMOVED--/system/priv-app/CellBroadcastReceiver

--REMOVED--/system/priv-app/CarrierConfig

--REMOVED--/system/priv-app/CallLogBackup

--REMOVED--/system/priv-app/BackupRestoreConfirmation

--REMOVED--/system/app/YouTube

--REMOVED--/system/app/WebViewGoogle

--REMOVED--/system/app/Wallet

--REMOVED--/system/app/Videos

--REMOVED--/system/app/UserDictionaryProvider

--REMOVED--/system/app/UpdateSetting

--REMOVED--/system/app/TimeService

--REMOVED--/system/app/talkback

--REMOVED--/system/app/SunBeam

--REMOVED--/system/app/shutdownlistener

--REMOVED--/system/app/qcrilmsgtunnel

--REMOVED--/system/app/PrintSpooler

--REMOVED--/system/app/PrebuiltNewsWeather

--REMOVED--/system/app/PrebuiltKeepStub

--REMOVED--/system/app/PrebuiltGmail

--REMOVED--/system/app/PrebuiltExchange3Google

--REMOVED--/system/app/PrebuiltDeskClockGoogle

--REMOVED--/system/app/PrebuiltBugleStub

--REMOVED--/system/app/PlusOne

--REMOVED--/system/app/PlayGames

--REMOVED--/system/app/Photos

--REMOVED--/system/app/PartnerBookmarksProvider

--REMOVED--/system/app/NfcNci

--REMOVED--/system/app/NewsstandStub

--REMOVED--/system/app/Music2

--REMOVED--/system/app/MediaShortcuts

--REMOVED--/system/app/Maps

--REMOVED--/system/app/LiveWallpapersPicker

--REMOVED--/system/app/LatinImeGoogle

--REMOVED--/system/app/KoreanIME

--REMOVED--/system/app/KeyChain

--REMOVED--/system/app/iWnnIME

--REMOVED--/system/app/HTMLViewer

--REMOVED--/system/app/Hangouts

--REMOVED--/system/app/GoogleTTS

--REMOVED--/system/app/GooglePinyinIME

--REMOVED--/system/app/GoogleHome

--REMOVED--/system/app/GoogleHindiIME

--REMOVED--/system/app/GoogleEars

--REMOVED--/system/app/GoogleContactsSyncAdapter

--REMOVED--/system/app/GoogleCamera

--REMOVED--/system/app/FitnessPrebuilt

--REMOVED--/system/app/FaceLock

--REMOVED--/system/app/EditorsSlidesStub

--REMOVED--/system/app/EditorsSheetsStub

--REMOVED--/system/app/EditorsDocsStub

--REMOVED--/system/app/Drive

--REMOVED--/system/app/DownloadProviderUi

--REMOVED--/system/app/DocumentsUI

--REMOVED--/system/app/DMAgent

--REMOVED--/system/app/CloudPrint2

--REMOVED--/system/app/Chrome

--REMOVED--/system/app/CaptivePortalLogin

--REMOVED--/system/app/CalendarGooglePrebuilt

--REMOVED--/system/app/CalculatorGoogle

--REMOVED--/system/app/Books

--REMOVED--/system/app/BasicDreams