1.糖同步：
SugarSync 是 J2 Global 提供的云服务和文件同步服务。它可以主动同步计算机系统和其他设备中的文件，以进行备份、访问和共享。它受 Windows、macOS、iOS 和 Android 操作系统支持。它由 J2 Global 于 2009 年推出。它不提供免费存储空间。它为付费用户提供有限和无限的存储空间。
2. Ubuntu 一：
Ubuntu One 是由 Canonical Limited 提供的文件托管服务、文件同步服务和云服务。这是一个基于 OpenID 的单点登录服务。它提供了在云上存储文件以及从云中传输音乐的服务。它由 Canonical Ltd 开发，适用于 Windows、OS X、iOS、Ubuntu 和 Android。它提供了 5 GB 的免费存储空间。它于2009年推出。
SugarSync 和 Ubuntu One 的区别：
| SUGARSYNC | UBUNTU ONE |
|---|---|
| It is owned by J2 Global. | It was owned by Canonical Limited. |
| It was launched in 2009. | It was also launched in 2009. |
| It does not offer free storage space. | It offered 5 GB free storage space. |
| It was developed by J2 Global. | It was developed by Canonical Ltd. |
| Maximum storage size is 60 GB for personal paid and unlimited for professional paid. | Maximum storage size was unlimited here. |
| It is still in use. | This service was suspended in 2014. |
| Files stored here are encrypted. | Files stored in Ubuntu One were not encrypted. |
| Maximum file size is not limited here. | Maximum file size was 5 GB per file. |
| It is a file hosting, file synchronization and cloud storage service. | It was a commercial file synchronization service. |
| It has traffic or band-width limit of 10 GB per day for free and 250 Gb per day for paid. | It has Amazon S3 limits as traffic or band-width limit. |
| It supports Windows, OS X, Android, OS, Blackberry and Windows Phone. | It supported Windows, OS X, Android, Ubuntu and iOS. |
| It does not have freeware version. | It had freeware version. |