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- Google-Backed Successor: ADT Self Setup — Google's official partner system, links directly to Nest cams and doorbells in the ADT+ app, cellular backup, optional pro monitoring.
- Best Overall DIY / Self-Monitored: SimpliSafe (Gen 3) (~$200 kit) — No contract required, robust long-range sensors, instant phone notifications, optional emergency dispatch.
- Best for Alexa & Ring Homes: Ring Alarm Pro (~$250 kit) — Built-in eero Wi-Fi 6 router, 24/7 backup cellular internet during outages, local video storage.
- Best No-Fee / Apple HomeKit: Abode Iota (~$280 kit) — Native Apple HomeKit, Zigbee, and Z-Wave support with zero required monthly subscriptions.
What I swapped mine for
I swapped my Nest Secure system for the SimpliSafe 8-Piece Wireless System.
The swap itself. The hardest physical part was peeling the old Nest Detect sensors off exterior door casings without ripping off the primer and paint. Use dental floss or light fishing line behind the double-sided foam tape to slice through the adhesive, then clean the trim with isopropyl alcohol before sticking up the new contact sensors. The SimpliSafe base station plugs into any central outlet with a built-in 24-hour backup battery, and the wireless keypad mounts with adhesive or two small wall anchors. The whole system took 35 minutes to pair and stick in place.
What carried over. Instant phone alerts whenever doors open, customizable home and away arming delays, and PIN-code keypad access for visiting contractors or dog walkers.
What changed. The biggest change is reliability independence. When Google pulled the plug on Nest Secure's servers on April 8, 2024, perfectly good hardware became paperweights overnight. SimpliSafe communicates locally over 433 MHz RF and includes built-in cellular backup that doesn't depend on Google maintaining a cloud subscription. Furthermore, because the Nest Guard secretly served as the Thread bridge for our Nest x Yale deadbolt, removing Guard meant adding a standalone Nest Connect plug-in bridge to keep remote lock control alive.
What it cost. ~$200 for the 8-piece kit (base station, keypad, 4 entry sensors, motion detector, and panic button). Zero ongoing monthly cost for self-monitoring.
The short version
The hub, sensors and fobs are dead. The cameras are fine. If you want to stay in Google Home, ADT Self Setup is the system Google backed after it killed Nest Secure, and it puts Nest cams and the Nest Doorbell in the same app as the door sensors. If you are done with Google, Ring Alarm for an Alexa house, SimpliSafe if you want no ecosystem at all, Abode if you run Apple Home or Home Assistant.
What Google actually killed on April 8, 2024
| Device | Status | What to do with it |
|---|---|---|
| Nest Guard (hub, keypad, siren) | Dead | Recycle. It also bridged the Nest x Yale Lock, so that lock lost remote access the same day. |
| Nest Detect (door and motion sensors) | Dead | Recycle. Proprietary radio, no other system reads them. |
| Nest Tag (key fob) | Dead | Recycle. |
| Nest Cam, Nest Doorbell, Nest Hub | Works | Keep. They live in the Google Home app and carry over to Path A. |
| Nest x Yale Lock | Works at the keypad | Needs a Nest Connect for remote access now. Guide here. |
Google announced the discontinuation in October 2020, invested in ADT the same year, and sent the shutdown date well ahead. Most owners I talk to did not read the email. If your alarm keypad went blank in April 2024, that is the whole story.
Step 1, inventory what you are protecting
- Count the openings. Every exterior door and every ground-floor window you had a Nest Detect on. That is your sensor count for any new system.
- List the Google gear that survives. Cams, doorbell, hubs, speakers. If this list is long, Path A keeps it all in one app. If it is one doorbell, you are free to leave.
- Decide on monitoring. Nest Secure sold professional monitoring through Brinks. Did you use it? If yes, you want a system with a real monitoring center. If you only wanted a phone alert, self-monitoring on any of the four paths is free or close to it.
- Check your insurance. Some carriers discount for monitored alarms and want a certificate. Only Paths A, B and C issue one.
Nest Secure replacement cost: 4 alarm platforms compared
Modern wireless alarm hardware is modular and priced without long-term contracts. The biggest cost factor is whether you want completely free self-monitoring with smartphone push alerts, or 24/7 UL-certified central station dispatch that satisfies homeowner insurance discounts.
| System | Ecosystems | Monthly Monitoring Fee | Starter Kit Cost | Best Use Case |
|---|---|---|---|---|
| SimpliSafe (Gen 3) 8-Piece | Standalone / Alexa / Google | $0 / mo (Self) or ~$22–$32 / mo (Pro) | ~$200 | Best DIY / zero mandatory subscription |
| ADT Self Setup | Google Home / ADT+ | $0 / mo (App) or ~$25–$35 / mo (Pro) | ~$240 | Official Google partner / Nest Cam integration |
| Ring Alarm Pro | Alexa / eero Wi-Fi 6 | $0 / mo (Local) or $20 / mo (Pro + Backup Internet) | ~$250 | Best for Alexa homes + 24/7 cellular Wi-Fi backup |
| Abode Iota | Apple HomeKit, Zigbee, Z-Wave | $0 / mo (Self) or ~$23 / mo (Pro) | ~$280 | Best native Apple HomeKit & smart hub pick |
Step 2, pick the right replacement path
Path A, stay in Google Home: ADT Self Setup
You have Nest cams, a Nest Doorbell, Nest Hubs. You want the door sensors in the same app as the video.
- What you get: a DIY kit, hub, keypad, door and motion sensors, that integrates with Google Home devices. Google invested in ADT in 2020 to make this the Nest Secure landing spot. Professional monitoring is optional and month to month.
- What changes: two apps during setup, ADT+ for the alarm and Google Home for the rest, with the Google devices visible inside ADT+. The keypad is ADT, not the round Nest Guard.
- The catch: ADT is a monitoring company. The kit is sold to get you on a plan. Read what self-monitoring includes before you buy the hardware.
- ADT direct, the Self Setup kits are sold there, not through Google.
Path B, Alexa household: Ring Alarm
Your house runs on Echo speakers and a Ring doorbell. You want arm and disarm by voice and a cheap monitored plan.
- What you get: the Ring Alarm kit, base station, keypad, contact and motion sensors, range extender. Z-Wave sensors, so third-party Z-Wave devices join too. Monitoring is a low monthly plan with no contract.
- What you give up: Google Home. Nest cams do not show up in the Ring app. If you keep them, you run two apps forever.
Path C, no ecosystem: SimpliSafe
You want an alarm that does not care which phone or speaker you own, with monitoring you can turn on and off.
- What you get: a SimpliSafe kit, the simplest install of the four. Sensors are peel-and-stick. Monitoring is month to month, and the cheaper plan gives you app control without a center.
- What you give up: deep smart-home integration. It talks to Alexa and Google for arm and disarm and not much else. That is the point.
Path D, Apple Home or Home Assistant: Abode
You left Google for Apple, or you run Home Assistant and want local control of the sensors.
- What you get: an Abode kit with HomeKit support and a Home Assistant integration. Z-Wave and Zigbee sensors. Optional monitoring.
- What you give up: the polish. Abode is the enthusiast pick. If nobody in the house wants to configure anything, take Path C.
Step 3, install it without a callback
- Pull the Nest Detects and the Guard first. Adhesive comes off with floss and a hair dryer. Patch the screw holes if you used screws. Do this before the new sensors go up so nobody mounts a new sensor next to a dead one.
- Mount contact sensors on the frame, magnet on the door. Gap under a quarter inch. On a metal door, use the spacer in the box or the magnet reads through the steel.
- Put motion sensors in corners, seven feet up, pointed away from windows and heat registers. A motion sensor aimed at a sunny window is the number one false alarm I get called for.
- Keypad near the door you actually use, not the front door you never open.
- Walk-test every sensor with the app open. Open each door, walk each room, watch each one report.
- Set entry and exit delays before you arm it for real. Thirty seconds is standard. Sixty if the garage door is the way in.
- Recycle the Nest hardware. Lithium cells inside the Guard and the Tags. Best Buy takes them.
What NOT to do
It is listed on eBay as if it works. It does not. The servers are off. There is no way to activate a Nest Guard, and a seller who says otherwise is wrong or lying.
Every path above sells month to month. A three-year contract for a free kit is the old alarm-industry model, and it is how people end up paying for a system in a house they sold.
Some kits sell a smoke listener that hears your existing alarms. That is a nice extra. It is not a smoke alarm. If your ceiling units are Nest Protect, read the Nest Protect replacement guide.
If you have an unusual setup
Nest x Yale Lock that was bridged through the Nest Guard
Your lock lost remote access on April 8, 2024. Google emailed eligible owners a free Nest Connect in January 2024. If you missed that, buy a Nest Connect or fold the lock into the same swap using the lock replacement guide.
Rental property
Get a system with a keypad code per tenant and no long contract. SimpliSafe or Ring. Change the codes at turnover, not the locks.
Large house or detached garage
Every kit above sells a range extender. Buy one if a sensor sits more than about 30 feet or two walls from the hub. A sensor that drops off the network is worse than no sensor, because you think it is there.
Related diagnoses
FAQ
Is Nest Secure still working?
No. Google shut it off on April 8, 2024. The Nest Guard, Nest Detect sensors and Nest Tag fobs no longer function. Nest cams, the Nest Doorbell and Nest Hubs still work in the Google Home app.
What is the official Nest Secure replacement?
ADT Self Setup. Google invested in ADT in 2020 after discontinuing Nest Secure, and the ADT+ system integrates Nest cams and the Nest Doorbell alongside its own door and motion sensors.
Can my Nest Detect sensors work with another system?
No. They use a proprietary radio that only the Nest Guard reads. Recycle them.
Why did my Nest x Yale Lock lose remote access in April 2024?
The Nest Guard doubled as the Thread bridge for the lock. When Nest Secure shut down, the bridge went with it. A Nest Connect restores remote access.
Do I need professional monitoring?
Only if you want a monitoring center to call the police, or your insurer wants a certificate. All four systems here work self-monitored with phone alerts for free or close to it.
Is it safe to buy a used Nest Secure?
No. The servers are off and there is no way to activate a Nest Guard. Any listing claiming it works is wrong.
What does a Nest Secure replacement cost?
A replacement DIY smart security starter kit typically costs between ~$200 and ~$280 for a base station, keypad, motion detector, and 4 door/window sensors. Self-monitoring via smartphone alerts costs $0 per month with SimpliSafe or Abode. Optional professional 24/7 emergency dispatch runs ~$20 to ~$35 per month with no long-term contracts.