Tax Days vs. Southbound
Southbound is the competitor closest to Tax Days in philosophy: iPhone-only, no servers, no accounts, low-power location rather than continuous GPS. So this comparison is not about privacy, because both take the same position. It is about scope and price. Southbound tracks Florida. Tax Days tracks all 50 states plus 200+ countries, Schengen, and the UK SRT. Here is the honest split. (Southbound's pricing and features below are taken from getsouthbound.com as of August 2026; it is free during early access, so confirm the current terms there.)
Pricing at a glance
Privacy-first iPhone app. No accounts, no servers. Optional iCloud sync via Apple's encrypted CloudKit.
iPhone app built for one job: proving days in Florida against the 183-day rule for people who moved there from a high-tax state. Uses low-power cell tower and Wi-Fi network changes rather than continuous GPS, keeps data on your iPhone and personal iCloud with no servers or accounts, and supports Apple Family Sharing.
Feature comparison
| Feature | Tax Days | Southbound |
|---|---|---|
| Annual cost | $29.99/year | Free during early access; $249/year stated for after |
| Cost today | $29.99/year, or free on the limited tier | Free while early access lasts |
| Jurisdictions covered | All 50 US states plus 200+ countries | Florida |
| The state you are leaving | Tracked, with that state's own residency test | Focused on presence in Florida |
| Tracking method | Significant-change monitoring (Pro) or manual entry | Cell tower and Wi-Fi network changes, low power |
| Manual trip entry | Yes, you can skip location entirely | Tracking is automatic by design |
| Data location | On your iPhone + optional iCloud, no accounts, no servers | On your iPhone + personal iCloud, no servers, no accounts |
| Family Sharing | Not advertised | Yes, up to five household members, separate records |
| Federal Substantial Presence Test | Yes (3-year weighted) | Out of scope |
| Schengen 90/180 | Yes | Out of scope |
| UK SRT | Yes | Out of scope |
| Export | Audit-ready PDF with a clear day-count trail | Not published |
| Platform | iPhone (iOS 26+), Mac via Catalyst | iPhone |
Which one is right for you?
Tax Days is best for…
- Anyone whose day count involves more than one state.
- People who travel internationally as well as domestically.
- Anyone who wants the state they left tracked with its own statutory test.
- People who want the option to log trips by hand with no location access at all.
Southbound is best for…
- People whose only question is whether they cleared 183 days in Florida.
- Households that want one subscription covering up to five people via Family Sharing.
- Anyone who wants a single-purpose app with nothing else in it.
- Early adopters, while it is still free.
Bottom line: Southbound and Tax Days agree on the hard part: your location history belongs on your phone, not on a vendor's servers, and low-power location beats continuous GPS. The difference is scope. If Florida is the whole question and you want one thing done simply, Southbound is a clean answer, and it is free while early access lasts. If you also need to defend the days you spent in the state you left, or you cross an international border, Tax Days covers all 50 states and the international rules for $29.99/year, well under the $249 Southbound has said it will charge after early access.
Frequently asked questions
How much does Southbound cost?
Southbound is free during its early access period. Its site states $249 per year after early access ends, billed annually through the App Store. Tax Days is $29.99 per year with a free tier that covers a limited set of rules. Check getsouthbound.com for the current terms, since early-access pricing by definition changes.
Does Southbound track states other than Florida?
Southbound presents itself as a Florida residency tracker, built around the 183-day rule for people who have moved to Florida from a high-tax state. If your situation involves counting days in New York, California, or any other state as well, that is outside what it advertises. Tax Days covers all 50 states with their specific statutory tests.
Which app is more private?
Neither, in any meaningful sense, and that is worth saying plainly. Both are iPhone apps with no user accounts and no vendor servers, both keep the record on your device with backup through your own iCloud account, and both use low-power location signals rather than continuous GPS. Tax Days additionally lets you turn location off entirely and log every trip by hand. Choose between them on coverage and price, not on privacy.
Is Southbound better for a snowbird?
Only if your day count runs one way. A snowbird usually has two problems: proving enough days in Florida and proving few enough days in the state they left, which often has its own statutory residence test and its own audit practice. Southbound addresses the first. Tax Days addresses both sides at once, which is generally where the audit risk sits.
Can I use Family Sharing with Tax Days?
Family Sharing is a feature Southbound advertises and Tax Days does not, so if one subscription covering several household members matters to you, that is a point for Southbound. Tax Days syncs a single person's record across their own devices through iCloud instead.
What if I already use Southbound?
If Florida is genuinely your only jurisdiction, there is no strong reason to switch. Consider Tax Days when a second jurisdiction enters the picture, when you want the state you left tracked against its own test, or when early-access pricing ends and $249 a year has to be justified against $29.99.
Ready to try Tax Days?
$29.99/year. No accounts. No tracking. Free tier with limited rules.