10-29 11:15:50.520: E/ArcGIS(700): url =http://myserver:8000/ArcGIS/rest/services/MyServices/MapServer
10-29 11:15:50.520: E/ArcGIS(700): java.lang.RuntimeException: Invalid SpatialReference.
10-29 11:15:50.520: E/ArcGIS(700): at com.esri.core.geometry.SpatialReference.nativeGetWKID(Native Method)
10-29 11:15:50.520: E/ArcGIS(700): at com.esri.core.geometry.SpatialReference.create(Unknown Source)
10-29 11:15:50.520: E/ArcGIS(700): at com.esri.core.geometry.SpatialReference.fromJson(Unknown Source)
10-29 11:15:50.520: E/ArcGIS(700): at com.esri.core.internal.c.g.a(Unknown Source)
10-29 11:15:50.520: E/ArcGIS(700): at com.esri.core.internal.a.a.n.b(Unknown Source)
10-29 11:15:50.520: E/ArcGIS(700): at com.esri.android.map.ags.ArcGISTiledMapServiceLayer.initLayer(Unknown Source)
10-29 11:15:50.520: E/ArcGIS(700): at com.esri.android.map.ags.ArcGISTiledMapServiceLayer$1.run(Unknown Source)
10-29 11:15:50.520: E/ArcGIS(700): at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:442)
10-29 11:15:50.520: E/ArcGIS(700): at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:305)
10-29 11:15:50.520: E/ArcGIS(700): at java.util.concurrent.FutureTask.run(FutureTask.java:137)
10-29 11:15:50.520: E/ArcGIS(700): at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1076)
10-29 11:15:50.520: E/ArcGIS(700): at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:569)
10-29 11:15:50.520: E/ArcGIS(700): at java.lang.Thread.run(Thread.java:856)
Take out the initExtent parameter from your layout xml file. You are using you own map service which is in a different spatial reference than the service provided in the HelloWorld sample. If you still want to set the initial extent in your layout xml file, then adjust the coordinates to the spatial reference of your map service.
SpatialReference wgs84 = SpatialReference.create("GEOGCS['GCS_WGS_1984',DATUM[.........]]);