Nexus 5 comes with a beautiful multi color notification light. This can be used to notify events when the screen is off. This feature is disabled by default and can be enabled from here:
You might need to configure the color of the light, frequency and other options in the specific application’s settings(like Whatsapp and Gmail), for which you want the notifications.
To make calls and use mobile Internet on your Nexus 5, you will need to insert an active micro SIM Card. If no card is inserted, the message “No SIM card” appears on the phone’s lock screen.
To insert the sim card you will need to eject the SIM card tray or slot. This is located in the right hand side of the phone. The eject button is a small hole just below the tray door(on the top below the Power on button).
Note: The solutions explained below can damage or brick your phone. Please exercise caution when implementing them. The author has tried most of these solutions but under expert supervision. If you are not sure about the solution please contact your Google Support
There seems to be a common problem in some Nexus 5 phones wherein the phone switches off and just refuses to start up. This happened to a colleague of mine too and here are my observations and possible solutions to the problem: