Message apps such as Signal will keep your exchanges private
Q: What are the advantages of using a messenger app like Signal? Does everybody I want to communicate with have to use it as well?
Signal is one of several communication apps that fully encrypt the conversations you have with other users. Keeping your exchanges private is the main advantage of using such a program.
Signal encrypts not only text messages but also voice and video calls, pictures and documents.
To benefit from the secure exchange, everyone in the conversation must use Signal, so you may need to persuade your friends to download the app and sign up for the service.
The free, open-source app is available for Android and iOS. Signal also has a desktop edition for Windows, Mac and Linux, but you first need to install the app on your phone and link it to your phone number.
Once you set up Signal on your phone, you can invite your friends to join you. While Signal doesn’t have stickers or some of the more whimsical features of other messaging apps, it does let you create a profile name and an avatar.
You can also set messages to disappear after a set amount of time.
Signal encrypts conversations “end to end” with the Curve25519, AES-256 and HMAC-SHA256 standards, so only your recipients get the messages — and nobody else along the way. Signal’s creators say the company doesn’t have access to the message contents and has placed the app’s source code on a public server for anyone who wants to poke around in it.
WhatsApp is a similar private messaging tool. However, it’s owned by Facebook, which has caused privacy advocates and others to voice concerns based on the company’s troubled track record with handling personal data.
Q: What is the difference between posting a video to Instagram or to IGTV?
Instagram, originally an app for posting square smartphone photos when it arrived in 2010, added support for 15-second video clips in 2013. The platform now allows videos up to 60 seconds in length, and the clips can be in the horizontal format.
Earlier this summer, Instagram announced its new stand-alone IGTV app for sharing longer video. However, IGTV videos have their own specific requirements. (People using the standard Instagram app can also watch IGTV content by tapping the TV icon in the top-right side of the screen.)
Basic IGTV videos can be between 15 seconds and 10 minutes long, with a maximum file size of 650 megabytes. Users with verified or larger, professional accounts can post videos up to 60 minutes in length, with a maximum file size of 3.6 gigabytes. The clips should be in the MP4 format, and longer videos — with their heftier byte sizes — must be uploaded from a computer instead of a smartphone or tablet.
More notably, videos for IGTV must be in the vertical (portrait) format, which means you hold the phone upright to capture and view them. The aspect ratio of the vertical video should be 9:16. The clips need a minimum resolution of 720p and a frame rate of at least 30 frames per second; you can adjust these preferences in the settings for a phone’s camera app.
You can upload your vertical video with the regular Instagram app or the separate IGTV app for Android and iOS, but you first need to create your own IGTV channel.
To do that, tap the IGTV icon at the top of the Instagram app (or just open the IGTV app). Tap the gearshaped Settings icon and select Create Channel. You can also create a channel and upload videos from your profile page on the Instagram desktop website.
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