As of today, the Particle API can only be accessed through the
api.particle.io domain. Access through the legacy domain
api.spark.io has been disabled.
I notified Particle users with web applications that made requests to the
api.spark.io domain of this planned end of life by email one month ago.
If you have a web application that stopped working because of the domain change, you must update it to make Particle API requests to the
api.particle.io domain. No other change should be necessary in your application as the functionality of the Particle API offered by
api.particle.io is identical. In particular, no changes to the firmware running on devices is necessary.