Hi I'm completely new at Xamarin and I have spent a lot of time trying to run this App, cause a I don't have any experience.
There's an App in my work made in VisualStudio 2015 (Version = 14.0.24720.0) and I'm trying to run in Visual Studio 2017.
I solved some conflicts but I just can't make it work, neither in the Android Simulator nor in my Phone (Samsung Galaxy S5 mini- API 19)
The App has no errors but have some warnings.
My company has not given me certificates, so my first question is if it's necessary to have a developer certificate or a distribution certificate in order to deploy the App in the Simulator or my phone? I just wanna be able to test it and then upload it to the AppStore and PlayStore.
Somebody can explain me what I'm doing wrong? 
This is what "Implementing on the device" windows shows me:
Target _Sign:
Deleting file "bin/Release/sv.proj.dgii-Signed.apk".
/Users/palacios/Library/Developer/Xamarin/android-sdk-macosx/build-tools/27.0.3/zipalign 4 "/Users/palacios/Downloads/Company/AppProj.Droid/obj/Release/android/bin/sv.proj.dgii.apk" "bin/Release//sv.proj.dgii-Signed.apk"
/usr/bin/java -jar /Users/palacios/Library/Developer/Xamarin/android-sdk-macosx/build-tools/27.0.3/lib/apksigner.jar sign --ks "/Users/Boss/Dropbox/Company/Android/Signing Keys/Company_android_xamarin-1.keystore" --ks-pass pass:"#xxxxxxxxx" --ks-key-alias AppProj --key-pass pass:"#xxxxxxxxx" --min-sdk-version 15 --max-sdk-version 27 /Users/palacios/Downloads/company/AppProj.Droid/bin/Release/sv.proj.dgii-Signed.apk
Failed to load signer "signer #1"
java.io.FileNotFoundException: /Users/Boss/Dropbox/Company/Android/Signing Keys/Company_android_xamarin-1.keystore (No such file or directory)
at java.io.FileInputStream.open0(Native Method)
at java.io.FileInputStream.open(FileInputStream.java:195)
at java.io.FileInputStream.(FileInputStream.java:138)
at java.io.FileInputStream.(FileInputStream.java:93)
at com.android.apksigner.ApkSignerTool$SignerParams.loadKeyStoreFromFile(ApkSignerTool.java:828)
at com.android.apksigner.ApkSignerTool$SignerParams.loadPrivateKeyAndCertsFromKeyStore(ApkSignerTool.java:719)
at com.android.apksigner.ApkSignerTool$SignerParams.loadPrivateKeyAndCerts(ApkSignerTool.java:659)
at com.android.apksigner.ApkSignerTool$SignerParams.access$500(ApkSignerTool.java:611)
at com.android.apksigner.ApkSignerTool.sign(ApkSignerTool.java:266)
at com.android.apksigner.ApkSignerTool.main(ApkSignerTool.java:89)
/Library/Frameworks/Mono.framework/External/xbuild/Xamarin/Android/Xamarin.Android.Common.targets(2605,2): error MSB6006: "java" exited with code 2.
Done building target "_Sign" in project "AppProj.Droid.csproj" -- FAILED.
Done building project "AppProj.Droid.csproj" -- FAILED.
Build FAILED.