Date created: 22 Sep 2024
Date updated: 27 May 2026
Several of the COROS firmware releases are problematic for the speedsurfing community. This page captures the various issues, listing the COROS firmware releases since the start of 2024 in reverse-chronological order.
The task of testing new firmware releases has become extremely onerous, so I have not done any testing since the 3.0808.0 release in 2025. It has subsequently come to light that 3.0910.0 is badly broken, so maybe all releases since Apr 2025 are also broken.
General advice for watches with broken firmware:
Downgrading your firmware:
Prior to reviewing the finer details on this page it is advisable to read the article about sampling rates and aliasing. It would also be beneficial to read the article comparing the windsurfing and speedsurfing activities on COROS watches.
This table is a summary of the COROS firmware releases since the beginning of 2024.
| Date | Listed | APEX 2 | APEX 2 Pro | VERTIX 2 | VERTIX 2S | |
|---|---|---|---|---|---|---|
| 3.1608.0 | 15 May 2026 | Y | ? | ? | ? | ? |
| 3.1508.0 | 31 Mar 2026 | Y | ? | ? | ? | ? |
| 3.1408.0 | 30 Jan 2026 | Y | ? | ? | ? | ? |
| 3.1308.0 | 15 Dec 2025 | Y | ? | ? | ? | ? |
| 3.1216.0 | ? | - | ? | ? | ? | ? |
| 3.1213.0 | 27 Oct 2025 | Y | ? | ? | ? | ? |
| 3.1208.0 | 23 Sep 2025 | Y | ? | ? | ? | ? |
| 3.1012.0 | 12 Aug 2025 | Y | ? | ? | ? | ? |
| 3.1011.0 | 28 Jul 2025 | Y | ? | ? | ? | ? |
| 3.1008.0 | 17 Jul 2025 | Y | ? | ? | ? | ? |
| 3.0910.0 | 3 Apr 2025 | Y | ? | ? | 😡👎 | ? |
| 3.0808.0 | 15 Jan 2025 | Y | ? | 😊🤙 | 😊🤙 | ? |
| 3.0807.0 beta | ? | - | ? | 😊🤙 | 😊🤙 | ? |
| 3.0709.0 | 3 Dec 2024 | Y | 😊🤙 | 😊🤙 | 😡👎 | 😡👎 |
| 3.0708.1113 beta | 13 Nov 2024 | - | - | - | 😊🤙 | 😊🤙 |
| 3.0708.0 | 15 Oct 2024 | Y | 😊🤙 | 😊🤙 | 😡👎 | 😡👎 |
| 3.0706.0 beta | ? | - | 😊🤙 | 😊🤙 | 😡👎 | 😡👎 |
| 3.0510.0 | 2 Aug 2024 | Y | 😐🤞 | 😐🤞 | 😐🤞 | 😐🤞 |
| 3.0508.0 | 15 Jul 2024 | Y | 😐🤞 | 😐🤞 | 😐🤞 | 😐🤞 |
| 3.0506.0 beta | ? | - | 😐🤞 | 😐🤞 | 😐🤞 | 😐🤞 |
| 3.0409.0 | 21 May 2024 | Y | 😡👎 | 😡👎 | 😡👎 | 😡👎 |
| 3.0408.0 | 10 May 2024 | Y | 😡👎 | 😡👎 | 😡👎 | 😡👎 |
| 3.0308.0 | 31 Jan 2024 | Y | 😊🤙 | 😊🤙 | 😊🤙 | ? |
The official COROS release notes are often out of date and do not mention significant changes in behaviour.
This table is a summary of the COROS firmware releases since the beginning of 2024.
| Date | Listed | APEX Pro | VERTIX | |
|---|---|---|---|---|
| 3.0808.0 | 19 Aug 2025 | Y | ? | 😡👎 |
| 3.0510.0 | 18 Jun 2025 | - | 😡👎 | 😡👎 |
| 3.0509.0 | ? | - | 😊🤙 | 😊🤙 |
| 3.0508.0219 beta | ? | - | 😊🤙 | 😊🤙 |
| 3.0508.0 | 15 Jul 2024 | - | 😡👎 | 😡👎 |
| 3.0409.0 | 21 May 2024 | Y | 😊🤙 | 😊🤙 |
| 3.0408.0 | 10 May 2024 | - | 😊🤙 | 😊🤙 |
| 3.0309.0 | 31 Jan 2024 | Y | 😊🤙 | 😊🤙 |
The official COROS release notes are often absent and do not mention significant changes in behaviour.
There have been four distinct behaviours for speedsurfing activities during 2024:
The 3.08xx.0 released have fixed the issues affecting the VERTIX 2 and VERTIX 2S with 3.07xx.0.
| APEX Pro | VERTIX | APEX 2 | APEX 2 Pro | VERTIX 2 / 2S | |
|---|---|---|---|---|---|
| 3.0808.0 | - | - | 2025-01-15 | 2025-01-15 | 2025-01-15 |
| 3.0807.0 beta | 2025-01-01 | 2025-01-01 | 2025-01-01 |
The beta release 3.0706.0 appears to fix the issues between May and Aug 2024, but only on the APEX 2 and APEX 2 Pro.
The VERTIX 2 + 2S are broken and have reverted back to the behaviour of 3.040x.0 in May 2024.
| APEX Pro | VERTIX | APEX 2 | APEX 2 Pro | VERTIX 2 / 2S | |
|---|---|---|---|---|---|
| 3.0709.0 | 2024-12-03 | 2024-12-03 | 2024-12-03 | ||
| 3.0708.1113 beta | - | - | 2024-11-13 | 2024-11-13 | 2024-11-13 |
| 3.0708.0 | - | - | 2024-10-15 | 2024-10-15 | 2024-10-15 |
| 3.0706.0 beta | - | - | 2024-09-13 | 2024-09-13 | 2024-09-13 |
The 3.05xx.0 releases exhibit issues because speedsurfing behaves much like windsurfing, which is non-doppler and thus prone to spikes.
Owners of an APEX Pro or VERTIX with firmware 3.050x.0 (released Aug 2024) are advised to downgrade to the 3.0309.0 firmware.
| APEX Pro | VERTIX | APEX 2 | APEX 2 Pro | VERTIX 2 / 2S | |
|---|---|---|---|---|---|
| 3.0510.0 | - | - | 2024-08-02 | 2024-08-02 | 2024-08-02 |
| 3.0508.0 | 2024-08-07 | 2024-08-07 | 2024-07-15 | 2024-07-15 | 2024-07-15 |
| 3.0506.0 beta | - | - | 2024-07-01 | 2024-07-01 | 2024-07-01 |
The 3.04xx.0 releases exhibit major smoothing issues on Airoha watches (APEX 2, APEX 2 Pro, VERTIX 2), reminiscent of Garmin watches in 2022.
The smoothing issues do not affect the Sony watches (APEX Pro, VERTIX).
| APEX Pro | VERTIX | APEX 2 | APEX 2 Pro | VERTIX 2 / 2S | |
|---|---|---|---|---|---|
| 3.0409.0 | 2024-06-06 | 2024-06-06 | 2024-05-21 | 2024-05-21 | 2024-05-21 |
| 3.0408.0 | 2024-05-xx | 2024-05-xx | 2024-05-10 | 2024-05-10 | 2024-05-10 |
The 3.03xx.0 releases exhibit the original behaviour, similar in many respects to the Garmin watches in 2024.
However, unique to the COROS is the temporal offset issue on the APEX 2, APEX 2 Pro, VERTIX 2 which causes fantasy alphas.
Owners of an APEX Pro or VERTIX with firmware 3.050x.0 (released Aug 2024) are advised to downgrade to the 3.0309.0 firmware.
| APEX Pro | VERTIX | APEX 2 | APEX 2 Pro | VERTIX 2 | |
|---|---|---|---|---|---|
| 3.0309.0 | 2024-01-31 | 2024-01-31 | - | - | - |
| 3.0308.0 | - | - | 2024-01-31 | 2024-01-31 | 2024-01-31 |