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The latest update of WhatsApp for iOS causes problems with links. Thus, WhatsApp 2.16.4 for iPhone crashes when we try to send a link to another contact.
Version 2.16.4 brings more problems to users than anything else. This version with no apparent news causes an error when sending links on iOS 9, whether we have a iPhone 6s or an iPhone 6.
The problem seems to only occur when sending links, and it doesn't show any type of error, but rather closes the app directlySuddenly we will find ourselves on the main screen when we try to send a link to a WhatsApp contact. At least when sending photos, videos or other types of messages, this error does not occur.
At the moment there is no possible solution if we have updated to WhatsApp 2.16.4 for iPhone. We will have to wait for a new update to fix this problem. We also don't know if it affects all users, but it probably does since complaints are plentiful.

This is not the first WhatsApp error on iOS
The reality is that this problem when sending links via WhatsApp is not the first in recent months. In March we saw that iOS 9.3 caused problems with some apps such as WhatsApp, Telegram or Chrome when trying to open links, causing the browser to stop working and blocking the terminal for a few seconds.
Apple had to release an update soon to fix the problem that affected a large part of its users. It will be necessary to see if this time the problem is corrected by WhatsApp soon since it is actually caused by its latest update.