Apple's iMessage app lets you know if your message has been read; the sender and recipient must be using iMessages on an iPhone or iPad and have read receipts enabled.
Check if your text was read on Google Messages
You must ask the recipient to enable the read receipts option in their Messages app. Only then can you see if the person has read your text.
Spyware can be used by anyone, not just hackers
One popular app, mSpy, boasts the ability to monitor text messages, calls and social media interactions. The app can be installed remotely on an iPhone if you have the proper iCloud credentials. For Android phones, someone will need to install it on the phone directly.
The recipient may have turned read receipts off if you don't see the 'Seen' text or the eye icon. Try sending the person a DM. If they respond and you never saw the 'Seen' feedback, they've turned their read receipts off.
DELIVERED = confirmation the message has reached the recipient's phone but fails to show if it has been "seen" yet. "Delivered" is a good sign. It means that the text is ready and waiting for them to open it.
If someone you're chatting with has turned off read receipts, send them a voice note. Even a one second one will do. If they open it, the ticks will turn blue. While the hack definitely works on Android phones, it's a bit pesky.
Go to Settings – Applications – Manage Applications or Running Services, and you may be able to spot suspicious looking files. Good spy programs usually disguise the file names so that they don't stand out but sometimes they may contain terms like spy, monitor, stealth, and so on.
That's because the texts are being sent to an ID that is listed as an iMessage receive ID on both devices. See Settings > Messages > Send & Receive > You can be reached by iMessage at: Correct this so each device has a unique ID.
Formal discovery requires a party to disclose anything asked by the other party which is relevant and within the control of the party. This includes text messages (unless they were deleted). Failure to answer discovery may result in the finding of contempt against the spouse.
It is one of the easiest methods on the list to read messages without being seen by the sender. You only have to turn on the airplane mode of your device or shut down the internet. After that, you can read the message, and it will not show the read receipt to the sender.
Go to Settings > Messages > Text Message Forwarding. If you don't see Text Message Forwarding, go to Settings > Messages.
If someone in your family is getting text messages meant for you, or vice-versa, it's probably because those devices are sharing the same Apple ID. This typically happens because, at some point, you all wanted to share content you bought from the iTunes store, including apps, games, music, movies, TV shows, and more.
When you send them an SMS and you get the "Delivered" notification underneath it, you weren't blocked. If you get a notification like "Message Not Delivered" or you get no notification at all, that's a sign of a potential block.
When someone switches to a new device that doesn't run on iOS, they may leave their phone number in the app. In that case, you may not get the “Delivered” tag if you message them, but the message bubbles will be blue.
Using iCloud to Spy on Spouse
Your spouse could spy on you through a shared iCloud account. Sharing an iCloud account with your spouse surrenders access to about everything on your iPhone. Your location, photographs, contacts, text messages, everything.
In conclusion, it is technically possible for someone to remotely hack an iPhone, but it is highly unlikely to happen to most users. The expensive software and specialized techniques required for remote hacking make it a viable option only for high-value targets.
Here's how to turn off read receipts for all your conversations on your iPhone or iPad: Go to Settings > Messages, then turn Read Receipts off.
Strange Messages in the Inbox
To check a spy app's status and connection, sometimes the monitoring side needs to send messages to the device. As a result, strange messages appear in your inbox, and you have no idea who sent them. Such messages can be an indicator that your iPhone is being tracked.
Two grey ticks actually means you're not blocked! It means your message has been sent and delivered to your contact's WhatsApp client, they just haven't read it yet. If you've been blocked, you'd only see one grey tick. If you want to block someone on WhatsApp, it's pretty easy.
If you see a single grey tick it means that the message you've seen has been delivered to the Whatsapp server. However, this doesn't necessarily mean it's been received on the receipt's device yet. This could mean their phone is switched off or without signal at the moment.
Delivered means that it's gotten to its destination. Read means that the user has actually opened the text in the Messages app.