Before the Salesforce Mobile App can be meaningfully enabled, the org must complete migration to Lightning Experience, because Salesforce Classic has no native mobile app equivalent at all — the Mobile App specifically renders Lightning Experience configuration, such as Lightning Record Pages and Lightning Apps built in App Builder, adapted for mobile devices, and none of this exists as a concept within Classic's older architecture. Attempting to enable genuine mobile access for an org still running primarily on Classic is not simply a matter of flipping a setting; there is fundamentally no Classic-compatible mobile experience to enable, since the entire mobile rendering model depends on Lightning-based configuration that a Classic-only org has never built. The correct first step is using Salesforce's own Lightning Experience Transition Assistant to assess and complete the migration to Lightning Experience, after which the standard Module 21 and Module 22 mobile configuration work becomes genuinely applicable and meaningful.

This is because the Salesforce Mobile App and desktop Lightning Experience share the SAME underlying Lightning Page configuration — a Lightning Record Page built once in App Builder, including its Standard Components, Dynamic Forms fields, and Component Visibility Rules, is not a desktop-only artifact requiring a separate mobile-specific rebuild, but rather a single configuration that both platforms render, each adapting the same underlying definition to their own device-appropriate layout, such as desktop's multi-column sidebar arrangement versus mobile's single-column, touch-optimized presentation. This means the significant majority of Module 21's App Builder work directly and automatically benefits mobile users as well, without additional configuration effort, though genuinely reviewing how a specific page renders in the Phone device preview remains a worthwhile verification step, since not every Component is guaranteed to be perfectly mobile-optimized by default even though the underlying configuration itself is shared rather than duplicated.

The Compact Layout's strict field limit is a deliberate design constraint, not an incidental technical limitation, because its entire purpose is powering the Highlights Panel — the small, prominent summary area shown at the very top of a record, which is especially critical on mobile where screen space is genuinely scarce and the Highlights Panel may be the ONLY information visible before a user needs to scroll further. If Compact Layouts allowed an unlimited or large number of fields, this would directly undermine their core purpose, since a Highlights Panel crammed with too many fields would no longer deliver the fast, at-a-glance summary it is specifically designed to provide, especially in the constrained space of a phone screen. The strict limit forces genuine prioritization discipline, requiring an Admin to consciously select only the handful of truly most-critical fields a user needs to see in one instant glance, which is precisely the design philosophy that makes Compact Layouts genuinely valuable for mobile-first users rather than just a smaller version of a full Page Layout.

An Object-Specific Quick Action is tied to a particular record's context, typically appearing on that record's page and used to create a related record with some context already pre-filled, such as creating a new Case directly from within a specific Account's page. A Global Action, by contrast, is available from ANYWHERE in the application, including the mobile app's dedicated "+" Global Actions menu, without being tied to or requiring navigation to any specific existing record first. A field-based mobile user would specifically need a Global Action in a scenario like just leaving a client meeting and wanting to immediately log a quick follow-up note or Task before the details are forgotten, but not yet knowing or having time to first navigate to the specific correct Account or Opportunity record that note should ultimately relate to — a Global Action lets them capture that information immediately from wherever they are, with the option to properly link it to a specific record later, rather than losing the moment while navigating through several screens first to find the right record context an Object-Specific Quick Action would require.

This assumption is risky because offline support in the Salesforce Mobile App is deliberately scoped and configured rather than being a blanket guarantee that every capability functions identically without connectivity — viewing previously-synced, recently-accessed records is generally well-supported offline, and certain simplified actions may work with changes syncing once connectivity returns, but more complex capabilities, particularly sophisticated Flow-based automation, genuinely require an active connection to execute fully and correctly, and creating relationships to or working with entirely new data that was never previously cached locally is fundamentally constrained by what the device actually has stored. An Admin should proactively set realistic expectations by clearly communicating to field users specifically what they CAN reliably rely on without signal, such as viewing recently-accessed records and using simplified, offline-aware Quick Actions, versus what genuinely requires connectivity, such as complex Flow automation or working with brand-new, not-yet-synced data — this kind of concrete, specific communication prevents frustrating, confusing surprises for a field user relying on the app in a genuinely low-connectivity moment.

Compact Layouts ensure the small handful of truly critical fields are visible in the Highlights Panel the instant a record opens, with zero scrolling required, directly serving a user who may only have a few seconds to glance at their phone before a client meeting begins. Mobile Navigation ordering ensures the Tabs and objects this specific field user needs most frequently are positioned early enough in the App's Navigation Items to appear directly in the constrained mobile bottom bar, reachable in one tap, rather than being buried behind an overflow "More" tap that adds friction to every single access. Global Actions provide a genuinely fast, context-free capture mechanism for the specific moments field work creates, such as needing to log a quick note immediately after leaving a meeting, before the details are forgotten and without the friction of first navigating to find the correct related record. Simply reusing desktop-optimized configuration is insufficient because desktop design assumptions, like a wide screen comfortably showing many fields and Tabs simultaneously with no real space constraint, do not transfer to mobile's genuinely limited screen real estate and the fundamentally different physical context of field work, meaning a page or navigation structure that works perfectly well on a desktop monitor can be genuinely unusable or frustrating for someone glancing at their phone screen for a few seconds between client visits.