IMO, the Salesforce Mobile App is the one thing that separates Salesforce from all other basic CRM systems - it is probably the ONLY reason you would use Contact Manager, Essentials, or Group Edition of Salesforce.

The new Lightning Mobile App looks great, but it takes a lot of setting up! So beware.

Firstly I would NOT start with the in-built tool to make everything in your org Mobile Enabled, unless it is a very simple org. It's too much. I may even decide to create a simplified Mobile app that includes ONLY the tabs that are helpful on Mobile. I used it, now I have to go back into every page and turn off Mobile so that I can turn off certain Apps to be available on Mobile.

The old Mobile App included EVERY single Tab that you have access to - there does not seem to be a way to turn that off. That is not good. As a System Administrator I would love to have a Mobile App that is just some key details that I would like to keep an eye on on Mobile, not the keys to the kingdom. But even if you create a simple App that only has a few tabs, you can still go to All Items. So annoying. I want nothing on Mobile unless I say so.

Edit each and every Lightning App

Only Lightning Apps are available on Mobile - you have set up Lightning Apps, haven't you? Go do that now!
Choose which ones will be available on Mobile, or Mobile and Desktop, or even Mobile only.
- However, it's not that simple. If you have a Lightning Page Layout that is Org Default then every App is going to be available on Mobile. The only other way around it is to have 2 lightning pages for every single lightning page, and that is NOT a work-around. This is highly annoying.

Edit each and every Object

Change all Compact Layouts to 10 Fields - note only 7 will show on the Desktop App and only 4 will show on the Related Record hover and Einstein Search so think carefully about which order you put fields in. Remember Phone and Email fields can group on Desktop.

Page Layouts

Edit each and every related list so that the first 4 fields are appropriate for Mobile. Eg I had to create a formula field that had the three fields that I need to see for on the Mobile app because there was another 3 fields I needed also. Then I had to put that field first in the list because no other fields other than the first field wrap text on the mobile. This is completely crap! So now my desktop layouts look like shit because I actually need it to function on the mobile also.
Remove Mobile Smart Actions on ALL pages except maybe Contact. It adds ridiculous things like New Opportunity to ALL your pages even though you may not use Opportunities.
Be sure to arrange the buttons in the right order. Now that the buttons are on top (stupid!) it might change the order you want them in, and of course you are going to want them in different order on the Mobile App and Desktop and you can NOT do that, so you need to compromise.
Use Quick Actions liberally!

Lightning Pages

Path is shit on Mobile... every time you even touch the page to scroll down it changes the path setting and you don't know what the value was until you leave the page without saving. Hide it.
Add your key Related List as a mobile only component right at the top of the page and set it to mobile only. It's one less click to get to the info you need.
Use Related Quick Links
The fact that you can't see Activity is just plain useless! Add a Report Chart of types of Activities instead.
Related Record Components will show on the page if they are not in a Tab (But the Optimisation report now says that every component should be in a tab or accordion). This is a nice way to show more details than the 10 in the Compact Layout, or different fields for different users. But hide any unnecessary Related Record Components.

Home Pages

It's funny that dashboards on home pages actually look really good on the mobile app.
As the App home page is the first button on the bottom left of the Mobile App, make it count. Add things there that are going to be useful for Mobile.

Favorites

WTF! Favorites are the second item on the bottom of the menu but every single Favorite is available for desktop only. Why show them? This is ridiculous! Help docs say "To be available as a favorite in the Salesforce mobile app, an object must have a tab that you can access in the app. Otherwise, you'll be prompted to view the object and its records on the full Salesforce site". But I DO have records that have a tab in the mobile app, and they STILL do not open! Even adding an actual tab from the actual mobile app as a favorite does not work! Another place where the documentation is stuffed!

Roll Out

There is a whole Trailhead on Planning your Roll Out Strategy and talking about Micro Moments and how to craft your mobile App to best suit the needs of your users. Sure, but if you can't hide MOST of the things that they can see in the main app anyway, how can you craft something that's mobile specific. You're just going to frustrate your users.

Navigation Settings

Here's what each menu item does.
I would put as few as possible.
I'm not sure what they are saying about Smart Search - is it used in the new app or not? Even this page doesn't tell me much, I thought Mobile Web wasn't a thing anymore? But Trailhead says don't remove it for Android. Weird. But with it removed in Android I can still search.
You still can't have different Mobile Only navigation for different people - apps help with that, but you still don't want too many apps.
You can turn it off now, using Custom Attributes on the Connected App - See https://help.salesforce.com/articleView?id=salesforce_app_customize_nav_menu.htm&type=5 but don't turn it off until you have set up EVERYTHING and assigned the new mobile app to EVERY user and you have covered off EVERY scenario that the Mobile default has.

What you can See

The Data Access and Views page is probably the most helpful to understand what is going on. Actually go through every document on this page, except there is NO documentation similar for the new Salesforce Mobile App, which is completely ludicrous!.

10 Fields in Highlights Panel
Back to the ridiculousness of only 4 fields in list views.
No Attachments!
No Mass Actions!
It says you can't Merge Accounts, but you can't even Merge Accounts in Lightning anyway unless there is a duplicate found.
If you want to convert Leads - check the restrictions.

Other Features

Salesforce Today

Oh what a complete waste of time feature. This page says it all. After reading that, I don't know why you would even bother with touching it. They basically say, it's broken, use it at your own discretion.

Security

There are some features you can set on the Connected App, but there is much more you can do to lock down Mobile Security - IF you pay for it. This is not good. Security should not be a paid feature.

I don't know how long this has been around, but you can now require a pin on the mobile apps - so that means you can use fingerprint authentication if your phone supports it. However I can NOT get it working on Android for fingerprint AND it does not support Face login for Android at all. But make sure ALL users' phones support it, or they will be annoyed with a pin and won't use the app.

The app now integrates with 1Password and LastPass - again, really good.

Offline

Does it work? Who knows... here's the docs. Read them. And note What's Available Offline.

You can have 7 objects to access for Offline. Would you even need 7? I picked 4 key objects.

From the Docs

If a user chooses not to customize their cache, Salesforce populates the user’s cache with up to 30 recently accessed records for their five most recently accessed objects. In addition to these records, the user’s tasks listed under My Tasks and their five most recently accessed dashboards are cached. However, if the user chooses at least one item from the Offline Preferences page, this selection replaces the existing cache with their new preferences.

quote

30! Is that all?!

Then remember to start the Cache.

From the Docs

TIP We recommend that your users populate their cache each time they log in to Salesforce so they have a meaningful set of available data when offline.

To me, something as bizarre as this means that they KNOW it's not working. You only need offline WHEN you are offline, you rarely plan to be offline.

Notifications

The new Notifications are really cool. You can name them, and the names of the notifications appear in the notification options and users can decide to turn them on or off. If you need Full Content Notifications, set that in the Connected Apps, but beware of your data privacy when you do that. ALSO remember to got to Salesforce Notifications menu and turn both options on, then go to Notification Delivery Settings and at the bottom of the page, choose your Custom Notification Type, click Edit in the drop down box, then choose your IOS and Android Apps. This also then ads a section in the Push Notification Settings in the mobile app where users can turn these custom notifications OFF!

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