diff --git a/src/source/build-numbers.md b/src/source/build-numbers.md
index 4862e42..d61961d 100644
--- a/src/source/build-numbers.md
+++ b/src/source/build-numbers.md
@@ -25,23 +25,23 @@
 The code names match the following version numbers, along with
 API levels and NDK releases provided for convenience:
 
-Code name      | Version      | API level
----------------|--------------|------------
-(no code name) | 1.0          | API level 1
-(no code name) | 1.1          | API level 2
-Cupcake        | 1.5          | API level 3, NDK 1
-Donut          | 1.6          | API level 4, NDK 2
-Eclair         | 2.0          | API level 5
-Eclair         | 2.0.1        | API level 6
-Eclair         | 2.1 (incl. 2.1-update 1) | API level 7, NDK 3
-Froyo          | 2.2.x        | API level 8, NDK 4
-Gingerbread    | 2.3 - 2.3.2  | API level 9, NDK 5
-Gingerbread    | 2.3.3 - 2.3.7            | API level 10
-Honeycomb      | 3.0                      | API level 11
-Honeycomb      | 3.1                      | API level 12, NDK 6
-Honeycomb      | 3.2 - 3.2.2              | API level 13
-IceCreamSandwich | 4.0.1 - 4.0.2          | API level 14, NDK 7
-IceCreamSandwich | 4.0.3                  | API level 15
+Code name        | Version       | API level
+-----------------|---------------|--------------------
+(no code name)   | 1.0           | API level 1
+(no code name)   | 1.1           | API level 2
+Cupcake          | 1.5           | API level 3, NDK 1
+Donut            | 1.6           | API level 4, NDK 2
+Eclair           | 2.0           | API level 5
+Eclair           | 2.0.1         | API level 6
+Eclair           | 2.1           | API level 7, NDK 3
+Froyo            | 2.2.x         | API level 8, NDK 4
+Gingerbread      | 2.3 - 2.3.2   | API level 9, NDK 5
+Gingerbread      | 2.3.3 - 2.3.7 | API level 10
+Honeycomb        | 3.0           | API level 11
+Honeycomb        | 3.1           | API level 12, NDK 6
+Honeycomb        | 3.2.x         | API level 13
+IceCreamSandwich | 4.0.1 - 4.0.2 | API level 14, NDK 7
+IceCreamSandwich | 4.0.3         | API level 15
 
 Starting with Cupcake, individual builds are identified with a short
 build code, e.g. FRF85B.
diff --git a/src/source/building-devices.md b/src/source/building-devices.md
index ec02238..c940475 100644
--- a/src/source/building-devices.md
+++ b/src/source/building-devices.md
@@ -89,6 +89,12 @@
 The procedure must be confirmed on-screen, and deletes the user data for
 privacy reasons. It only needs to be run once.
 
+Note that on the Nexus S, Nexus S 4G, Motorola Xoom and on Galaxy Nexus,
+all data on the phone is erased, i.e. both the applications' private data
+and the shared data that is accessible over USB, including photos and
+movies. Be sure to make a backup of any precious files you have before
+unlocking the bootloader.
+
 On Nexus One, the operation voids the warranty and is irreversible.
 
 On Nexus S, Nexus S 4G, Xoom, and Galaxy Nexus,
@@ -96,7 +102,7 @@
 
     $ fastboot oem lock
 
-Note that this erases user data on Xoom.
+Note that this erases user data on Xoom (including the shared USB data).
 
 ## Obtaining proprietary binaries ##
 
@@ -276,3 +282,12 @@
 manually re-activated after each factory reset.
 
     $ adb shell su root radiooptions 8 *22899
+
+## Restoring a device to its original factory state ##
+
+Factory images for Galaxy Nexus are available from
+[Google's factory image page](http://code.google.com/android/nexus/images.html).
+
+Factory images for the Motorola Xoom are distributed directly by Motorola.
+
+No factory images are available for Nexus S and Nexus One.