1. 安卓 1.1：
Android 1.1 是继Android 1.0 之后Google 推出的第二个Android 版本。它具有以前版本(即 Android 1.0)中包含的所有功能，并且在此版本中还添加了更多功能。在呼叫者应用程序中添加了一些功能，例如隐藏和显示数字键盘。此版本还增加了保存彩信附件的功能。它也没有像 Android 1.0 那样的正式版本名称，但非正式地称为Banana Bread 。 Android 1.1 中的 API 级别为 2。它于 2009 年 2 月 9 日发布。
2. 安卓 2.1：
Android 2.1 是继 Google 推出的 Android 2.0.1 之后的下一个 Android 版本。它具有以前版本的所有功能，并且在此版本中还添加了一些新功能。此版本与之前的 Android 2.0 和 Android 2.0.1 版本非常相似。此版本中没有添加任何主要功能。仅更新了用户界面。这个版本有一个版本名称。它的版本名称是Eclair 。 Android 2.1 中的 API 级别为 7。它于 2010 年 1 月 12 日发布。
Android 1.1 和 Android 2.1 之间的区别：
| S.No. | ANDROID 1.1 | ANDROID 2.1 |
|---|---|---|
| 1. | It is the second version of Android. | It is the next version of Android introduced after Android 2.0.1 version. |
| 2. | It is successor to Android 1.0 version. | It is successor to Android 2.0.1 version. |
| 3. | It is predecessor to Android 1.5. | It is predecessor to Android 2.2. |
| 4. | It was released on 9 February 2009. | It was released on 12 January 2010. |
| 5. | The API level in Android 1.1 version is 2. | The API level in Android 2.1 version is 7. |
| 6. | It does not have official version name like its successors. | It has official version name like its previous version. |
| 7. | It has unofficial version name ‘Banana Bread’. | It has official version name ‘Eclair’. |
| 8. | It had all the features of previous version and two more features were added in this version. | It had all the features of Android 2.0 and Android 2.0.1 but some new features were added in this version. |
| 9. | Ability to show and hide numeric key-board was introduced in this version. | It had updated user interface than its previous versions. |