Your inbox rate dipped last week and you have two tabs open: Brain and GlockApps. Both sit in the same category, but they answer different questions in very different ways. This comparison breaks down how each works, what each does well, and which one fits your situation.
How each tool works
InboxStack Brain — always watching
Brain watches your sending domains and IPs across Gmail, Outlook, and Yahoo, 24/7. When your inbox rate moves, it raises an incident on its own, runs the diagnosis engine to find the cause, and tells you exactly what to fix.
Brain tracks 30+ data points at once: SPF, DKIM and DMARC pass rates, how Gmail and Outlook score your domain and IPs (Google Postmaster, SNDS, Sender Score), bounce patterns, complaint rates, blacklist status, and inbox rate per mailbox provider. You never run a test to learn something is wrong — Brain is always watching. See how it works →
GlockApps — a seed test on demand
GlockApps uses a seed list: you send an email to a set of test addresses across mailbox providers, and GlockApps reports where each one landed — primary inbox, spam, or the promotions tab. It is a snapshot of where your email lands at the time of the test.
That is a useful check. If you are about to send a big campaign and want to know where it lands before pressing send, a GlockApps test tells you. It also helps you work out whether content or a technical fault is pushing you to spam at one specific provider.
Feature comparison
| Feature | InboxStack Brain | GlockApps |
|---|---|---|
| How it watches | Continuous, real-time 24/7 | On-demand seed tests |
| Real-time alerts | Yes — the alert system raises incidents on its own | No — manual test required |
| Finding the cause | Yes — the diagnosis engine + RCA Inspector | No — shows where it landed, not why |
| MBP coverage | Gmail, Outlook, Yahoo — live data | Major MBPs via seed list snapshots |
| SPF, DKIM, DMARC checks | Continuous pass rates and record health | Partial — included in test reports |
| How Gmail and Outlook score you | Real-time Postmaster, SNDS, Sender Score | Not included |
| Blacklist checks | Continuous across major RBLs | Partial — in some plans |
| Incident management | Yes — War Room, Resolution Center | No |
| Pre-send seed testing | 20–100 / mo on Brain & Command | Yes — core use case |
| Pricing | Free 30-day trial — talk to us for a plan | Pay-per-test or subscription from ~$59/mo |
| Free trial | 30-day full access, no card | Limited free plan |
When to choose Brain
Brain is the right call when you need to know what is happening to your inbox rate right now — not just when you remember to run a test.
- You send regularly at scale — ESPs, SaaS companies, and high-volume teams where a drop can hit thousands of emails before anyone notices.
- You want to diagnose, not just detect — Brain doesn't just say your inbox rate dropped; it tells you which number moved first and why.
- You manage multiple domains — watching every domain around the clock beats running manual tests on each.
- You need post-incident proof — Resolution Center and Outcome Tracker confirm whether a fix actually worked.
- You're an ESP or agency — multi-tenant workspaces and white-label reports let you watch every client domain from one dashboard.
When to choose GlockApps
GlockApps earns its place in the toolkit as a pre-send check. It fits when:
- You send infrequent large campaigns and want to know where they land before hitting send.
- You're troubleshooting a content issue — useful for isolating whether specific content trips the filters at one particular MBP.
- You need a low-cost entry point for occasional checks without a subscription.
- You already have something watching your sending and need a test tool alongside it.
Can you use both?
Yes — they cover different layers. Brain watches, alerts, and finds the cause. GlockApps tells you where a single email lands before you send it. Teams with high volume often run both: Brain for the day-to-day, GlockApps for campaign-level spot checks. Brain also includes 20–100 seed tests per month on the Brain and Command tiers, which covers the common pre-send case without a second tool.
If budget forces you to pick one, Brain covers the bigger gap: most spam-folder problems are invisible until they have already cost you, and something that watches around the clock catches them before that happens.
The verdict
GlockApps is a solid seed-test tool — useful for pre-send checks and content troubleshooting. Brain is a different product: it watches your sending 24/7, spots the drop, finds the cause, and walks you through the fix. If you want to know before your client does, rather than after a spot check, Brain is built for that job.
Still weighing options? Read the full buyer's guide →