IOS 7 Only Allows Find My iPhone with Primary iCloud Account

Question

While iOS7 may be a big leap forwards in most respects, the "Find my iPhone" feature has taken a big step in reverse. This useful feature is NO LONGER AVAILABLE for use with secondary iCloud accounts, ONLY your PRIMARY account.
This may not be a huge concern for most users, because many (including most first-tier tech reps at Apple I've spoken to) seem to believe that you can only have one iCloud account on a device. NOT TRUE. While you can only have one PRIMARY account, you can add multiple additional iCloud EMAIL accounts (go to Settings/Mail, Contacts & Calendars/Add Account/iCloud). In the last iOS, once you created a new, secondary iCloud email address, you could activate many iCloud features for use with the new account, including Mail, Calendar, Contacts, Reminders, Notes, Safari Data (which never actually worked), and Find My iPhone. Under iOS7, however, Find My iPhone is no longer available. Instead, a small paragraph below the new iCloud email account setup screen says "Only your main account can use Bookmarks, Photo Stream, Documents & Data, Backup, and Find My iPhone."
Consider two cases where this is a huge problem.
1) We have a large number of company iOS devices that we need to keep track of.
2) Personally, I have an iPhone and iPad, and so does my wife. So do our kids!
In both the above cases, we created a secondary iCloud account, we'll call it "[email protected]", and added it as a secondary iCloud email address on ALL our iOS devices. In the setup screen we disabled everything EXCEPT "Find My iPhone". This account has a unique password, making it possible to see the location of ANY OR ALL the devices using the Find My iPhone App, WITHOUT having to share email, contacts, calendars, etc. among all these devices.
In our company, I can tract the location of any iOS device I gave to an employee, but his personal PRIMARY iCloud account is used to keep his mail, contacts, calendars, etc. secure. He shares this data between his iPhone and iPad, but NOT with everyone else. In my family, we all have our own primary iCloud accounts. I share mine between my iPhone and iPad; my wife and kids do the same. This allows us to keep our calendars, contacts, emails, etc. separated. But we all used the secondary iCloud email account ONLY with Find My iPhone. This allowed everyone in the family to see the location of everyone else, very nice in an emergency. Unlike the Find My Friends app, the device being located doesn't have to respond to a request to be found (very important when finding a lost or stolen device).
In both the above cases, we just log into the Find My iPhone APP on ANY iOS device, using the secondary iCloud account's email address and password (the email address is actually saved in the app, so you really only need to enter the password after the initial login). Viola! You can now see the location of any device that has that secondary iCloud account installed. And a person can still be untrackable if they wish, simply by turning off the Find My iPhone feature under the shared account's iCloud account settings on their device.
Alas, with iOS7 this is no longer possible. With the Find My iPhone feature only available for use with the device's PRIMARY iCloud account, there are only two ways to track another device:
1) Use the same primary iCloud account (which forces you to share other data and features you may not want to);
2) Log into the Find My iPhone APP with the PRIMARY iCloud email address and password of the person you want to track.
Either way, the person doing the tracking MUST have access to the PRIMARY iCloud credentials of the device they are tracking. This is a large security hole! Ask yourself: if you are a parent, do you really want your kids to have access to your primary iCloud account, including your mail, contacts, calendars, etc? Some people may not want their spouse to access that. In a company setting, do you want all your employees to be FORCED to share Documents & Data, Backup and Bookmarks, just to use the Find My iPhone feature? If they want to keep their mail, contacts, calendars, etc. separated from other employees, they will be forced to move these to a secondary iCloud account, which will no longer allow them to share Bookmarks, Photo Stream, Documents & Data or Backup. Why this ridiculous limitation?
The bottom line:Find My iPhone is now only useful for the primary iCloud account holder, and can no longer be used effectively between larger numbers of iOS devices, such as families or corporate institutions. This should be addressed in the next update to the iOS.

Answer 1

Brad, and everyone else, just to clarify my original post that started this thread, and offer a workaround or two: you CAN  still locate, erase etc. any iOS device using Find My iPhone in iOS7,  but the device you want to track or erase must EITHER use the same PRIMARY iCloud account as you do, OR you must log into the Find My iPhone app on your phone using THEIR primary iCloud account's username and password.
For parents, that's not a big deal, maybe just an annoyance: give your kids their own individual primary iCloud accounts, but you jot down their username and password in their contact info on your phone. Log Into FMI with that and track them.
The real pain is if you as an adult want others to be able to see where you are, WITHOUT also giving them access to your other iCloud info. For then to see you, THEY must either use the same PRIMARY iCloud account as you do, or they must have your username and password to log into the FMI app...which means they cal also see all your other stuff, even if you turn off the FMI feature on your phone. Anything you share with iCloud will be visible to anyone with access to your iCloud account.
For corporate users who want to track and manage company-owned iOS devices without having all of them use the same primary iCould account, this is a big pain. For families, imagine being on a vacation, or experiencing a disaster, accident, etc, where you'd really want everyone to be able to locate each other, even if they are unable to answer their phone or otherwise respond...a very real possibility in today's world. Now not so easy without compromising privacy and security.
I have three workarounds. The first two use Find My iPhone and so require everyone to use the same PRIMARY iCloud account.
1) the simplest thing is to go to your device under Settings/iCloud and toggle off anything you don't want others to see...but if you have multiple devices of your own (say an iphone and an iPad), this prevents you from sharing with yourself. Bummer.
2) It occurred to me today that with iOS6 there was a way to lock out changes to features in Settings. Sure enough, it still works with iOS7. Enabling this feature allow everyone to share the same PRIMARY iCloud account WITHOUT sharing other things you'd like to keep private. Enabling this feature will prevent the person with the device from making any changes to the Accounts on their device (Mail, Contacts, Calendars), so you'll need to think about what features of these accounts you WANT to allow before following the steps below. ALL THE FOLLOWING STEPS ARE PERFORMED ON THE OTHER DEVICES IN YOUR FAMILY/COMPANY, not your own.
A) I suggest entering airplane mode in Settings to prevent the device you are working on from downloading any of your iCloud info during this process.
B) Next, be sure YOUR PRIMARY iCloud account is listed on the person's device that you wish to track (kid's employee, etc). Go to Settings/iCloud to check this, and if necessary sign out of their iCloud account here and sign in with your primary iCloud account.
C) Add a second iCloud account using their personal iCloud email address (the one you just deleted as the primary). Set this one to share whatever they need to (their own Mail, contacts, calendars, etc). If they weren't previously using iCloud for anything but tracking and already had their own email account set up, you can omit this step.
D) Now, decide what features of your Primary iCloud account you do NOT want this person to be able to see or use  (mail, contacts, calendars, etc). On THEIR DEVICE go to Settings/iCloud, and toggle OFF any of these things, but be sure to leave anything they need to share. A common issue here will be Photos. Since Photo sharing is now ONLY supported with the primary account, I suggest leaving this on, but you can still prevent them from seeing your new photos if needed. Tap the arrow to the right of Photos, and on the next screen toggle off "My Photo Stream", but leave on "Photo Sharing" which allows them to see, create and subscribe to other shared steams, just not your primary photostream. You can instead make this same Photo setting on your device, which has the same result. Or just disable Photos altogether. Whatever setting suits you the best.
Once you have decided which features of your primary iCloud account you'll allow this person to see, BE SURE YOU HAVE ALSO TURNED ON "Find My iPhone" here.
E) Lastly, go to Settings/General/Restrictions. Tap "Enable Restrictions". Enter a new password (twice- this is NOT the same password for the device, but only for locking and unlocking restrictions, so use a new one only you will know). Scroll down to the "Allow Changes" section and tap "Accounts." Tap to place a check next to "Don't Allow Changes". Exit from Settings.
You're done! Repeat the above steps on every device in your family or company you want to track. You will now be able to track all of them at one time using Find My iPhone on your device, from your primary iCloud account, and they will also be able to see your device location, but they will not be able to see any of your information as long as you toggled it off and then locked out account changes under restrictions. Be aware that they will not be able to add, delete or change any Mail accounts unless you unlock the restrictions. But you will likely have their own separate email account on this device (step C above).
3) if this is too much for you to handle, and tracking is your primary concern,  in the App Store there is a free app called "Find my Kids - Footprints" . They just released a new iOS7 version which is unrated, but the previous version was reasonable well rated. After a trial it requires an annual subscription (which removes the ads, and it is VERY cheap), but it irks me to pay for a service that I used to get for free.  I haven't tried it yet, but it seems to do a bit more that the Find my iPhone app as far as tracking...but it can't lock or erase your device. You'd still need to use their primary iCloud account for that. I'm sure we'll be seeing more apps like this in the near future.
Hope this helps.