DANGER!
First, I'm a big supporter of Primal, and I know why they've compromised and used a permissioned & centralized API like Spark for their wallet. It might be the best choice for many of their users.
But also, you need to realize when you use Spark, you are trusting one very politically active, very wealthy, family (the Marcus family)..... to custody your funds, approve your transactions, and monitor your transactions.
When Primal says that your Spark wallet is "non-custodial" - this is basically a legal fiction. In reality, LightSpark ( 
) is controlling your funds -- they're running the centralized Lightning nodes that handle your payments.
Again: For some users this might be fine.
But if you are not a supporter of the state of Israel ... or ... if you are engaged in anything where you need privacy, or, for example, you don't want your data shared with certain governments..... please be very cautious with Spark.
More details: 
Global Payments Platform | Instant Bitcoin & Fiat Transfers | Lightspark
Send and receive any currency—fiat or crypto—anywhere in the world with Lightspark's simple APIs. Real-time, low-cost global payments infrastru...
GitHub
No clear way to run an SSP without a business relationship with LightSpark? · Issue #64 · buildonspark/spark
This project seems to be gaining momentum and there are community concerns that both SSPs (lightspark, flashnet) are controlled by the same family....
