The feature is not strictly necessary, and was in fact, removed earlier from the mobile version.
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The recent purpose has to do with the new Offline capability of the site. The clock is Green when the system is Online. When you are Offline (in Sawaari mode), the clock turns red and the time indicated shows when the page was last saved (not the current time). This Green/Red aspect of the clock is also present in the desktop version. In Offline mode, the clock is red, and shows when the page was last...
more... saved.
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The clock can be removed, or be displayed optionally in the mobile version, in the upcoming versions.